<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03754556</url>
  </required_header>
  <id_info>
    <org_study_id>19682</org_study_id>
    <nct_id>NCT03754556</nct_id>
  </id_info>
  <brief_title>Study on Medical Records of Women Using an Intrauterine Device (IUD) to Analyze the Risks That the IUD Will be Expelled or Perforates the Womb in Relation to Breastfeeding, the Point in Time When the IUD Was Inserted After Childbirth and in Relation to Different Types of IUDs</brief_title>
  <acronym>APEX IUD</acronym>
  <official_title>Study on the Association of Uterine Perforation and Intrauterine Device (IUD) Expulsion With Breastfeeding Status at the Time of IUD Insertion and Postpartum Timing of IUD Insertion in Electronic Medical Record Databases - A Postmarketing Requirement for Mirena</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Bayer</agency>
      <agency_class>Industry</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Bayer</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Study to analyze electronic medical records of women using an intrauterine device (IUD). The&#xD;
      study was required by the FDA for the marketed IUD Mirena (US Post-marketing requirement;&#xD;
      short name of study: APEX IUD).&#xD;
&#xD;
      The study analyzed the risks that the IUD was expelled or perforated the womb for the&#xD;
      following group comparisons:&#xD;
&#xD;
        -  Women who were breastfeeding at the time of IUD insertion and within 52 weeks postpartum&#xD;
           versus women who were not breastfeeding at the time of IUD insertion and within 52 weeks&#xD;
           postpartum.&#xD;
&#xD;
        -  Women who had a first observed IUD insertion within different time periods after&#xD;
           childbirth (i.e., ≤ 6 weeks, &gt; 6 weeks and ≤ 14 weeks, &gt; 14 weeks and ≤ 52 weeks) versus&#xD;
           women who had their first observed IUD insertion more than 52 weeks after childbirth,&#xD;
           including women without a recorded delivery within the past 52 weeks. An additional&#xD;
           analysis involved 5-level postpartum timing (i.e., 0 to 3 days, 4 days to ≤ 6 weeks, &gt; 6&#xD;
           weeks to ≤ 14 weeks, &gt; 14 weeks to ≤ 52 weeks) versus the &gt; 52 week postpartum group.&#xD;
&#xD;
      The study also analyzed the risks that the IUD was expelled or perforated the womb for&#xD;
      different types of IUDs. In addition, the study aimed to assess the following interactions:&#xD;
&#xD;
        -  The extent to which the type of IUD (IUDs releasing the hormone LNG versus Copper IUDs)&#xD;
           modified the risk that an IUD was expelled or perforated the womb in relation to&#xD;
           breastfeeding and/ or in relation to the point in time when the IUD was inserted after&#xD;
           childbirth.&#xD;
&#xD;
        -  The extent to which the breastfeeding status modified the risk that an IUD was expelled&#xD;
           or perforated the womb in relation to the point in time when the IUD was inserted after&#xD;
           childbirth.&#xD;
    </textblock>
  </brief_summary>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">December 3, 2018</start_date>
  <completion_date type="Actual">November 29, 2019</completion_date>
  <primary_completion_date type="Actual">November 29, 2019</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Cohort</observational_model>
    <time_perspective>Retrospective</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Crude Incidence Rate of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Cumulative Incidence of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Breastfeeding Status and Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of uterine perforation among women who were not breastfeeding at the time of first observed IUD insertion</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Crude Incidence Rate of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Cumulative Incidence of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Postpartum Timing and Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity scores and breastfeeding status, to evaluate whether the risk of uterine perforation among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of uterine perforation among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt; 52 weeks postpartum</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion &gt;14 weeks postpartum or with no recorded delivery</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion &gt; 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt;36 weeks postpartum or with no recorded delivery</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Incidence Rate Ratio (IRR) for Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Adjusted for propensity score, overall and stratified by breastfeeding status at the time of IUD insertion for ≤ 36 weeks postpartum at IUD insertion versus &gt; 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up. Reference group: &gt; 36 weeks or no delivery</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Incidence Rate Difference (IRD) for Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Propensity score-adjusted incidence rate differences (per 1,000 person-years) for uterine perforation for women ≤ 36 weeks postpartum at IUD insertion compared with those who were &gt; 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status. Reference group: &gt; 36 weeks or no delivery</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Crude Incidence Rate of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Cumulative Incidence of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for IUD Type and Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of uterine perforation among women with copper IUD at the time of first observed IUD insertion</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Crude Incidence Rate of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Cumulative Incidence of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Menorrhagia Status and Uterine Perforation-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of uterine perforation among women who do not have this indication</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Effect Modification of Breastfeeding Status on Postpartum Timing for Uterine Perforation</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted hazard ratios to evaluate the extent to which breastfeeding status (yes vs. no) modified the association of uterine perforation for women with IUD insertion at different time periods postpartum (i.e., IUD insertion ≤ 14 weeks versus IUD insertion &gt; 14 weeks postpartum) among women with a recorded delivery within the past 52 weeks at the time of the first observed IUD insertion</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Effect Modification of IUD Type on Breastfeeding Status for Uterine Perforation</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Effect Modification of IUD Type on Postpartum Timing for Uterine Perforation</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, &gt; 6 and ≤ 14 weeks, &gt; 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, &gt; 52 weeks or no delivery</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Crude Incidence Rate of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Cumulative Incidence of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Breastfeeding Status and IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted to evaluate whether the risk of IUD expulsion among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of IUD expulsion among women who were not breastfeeding at the time of first observed IUD insertion</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Crude Incidence Rate of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Cumulative Incidence of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Postpartum Timing and IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity score and breastfeeding status, to evaluate whether the risk of IUD expulsion before and after 49 days of insertion among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of IUD expulsion among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks Reference group: IUD insertion &gt; 52 weeks postpartum</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion &gt;14 weeks postpartum or with no recorded delivery</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion &gt; 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt;36 weeks postpartum or with no recorded delivery</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Incidence Rate Ratio (IRR) for IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Overall and stratified by breastfeeding status at the time of IUD insertion for IUD expulsion for ≤ 36 weeks postpartum at IUD insertion versus &gt; 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up Reference group: &gt; 36 weeks or no delivery</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Incidence Rate Difference (IRD) for IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Adjusted incidence rate differences (per 1,000 person-years) for IUD expulsion for women ≤ 36 weeks postpartum at IUD insertion compared with those who were &gt; 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status Reference group: &gt; 36 weeks or no delivery</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Crude Incidence Rate of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Cumulative Incidence of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for IUD Type and IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score adjusted to evaluate whether the risk of IUD expulsion among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of IUD expulsion among women with copper IUD at the time of first observed IUD insertion</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Crude Incidence Rate of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Cumulative Incidence of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions</measure>
    <time_frame>At 1 year and 5 years of follow-up</time_frame>
    <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adjusted Hazard Ratio (HR) for Menorrhagia Status and IUD Expulsion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score adjusted to evaluate whether the risk of IUD expulsion among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of IUD expulsion among women who do not have this indication</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Effect Modification of IUD Type on Breastfeeding Status for IUD Expulsion</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Effect Modification of IUD Type on Postpartum Timing for IUD Expulsion</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, &gt; 6 and ≤ 14 weeks, &gt; 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, &gt; 52 weeks or no delivery</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Number of Indicators of a Potentially Difficult Insertion, Overall, by Breastfeeding Status, and by Postpartum Timing of IUD Insertion-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Number of Indicators of a Potentially Difficult Insertion, Overall, by IUD Type and by Menorrhagia Status-first Observed IUD Insertions</measure>
    <time_frame>Up to 11 years</time_frame>
    <description>To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)</description>
  </secondary_outcome>
  <number_of_groups>1</number_of_groups>
  <enrollment type="Actual">326658</enrollment>
  <condition>Intrauterine Devices</condition>
  <arm_group>
    <arm_group_label>Women with IUD</arm_group_label>
    <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Intrauterine device</intervention_name>
    <description>Intrauterine devices, e.g. BAY86-5028 (Mirena, Skyla, Kyleena), Liletta and ParaGard</description>
    <arm_group_label>Women with IUD</arm_group_label>
    <other_name>Levonorgestrel, Copper IUD</other_name>
  </intervention>
  <eligibility>
    <study_pop>
      <textblock>
        Women with IUD-insertion&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Non-Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Women with evidence in the database of insertion of an IUD (e.g.&#xD;
             levonorgestrel-releasing, copper) during the study time window for each site&#xD;
&#xD;
          -  Enrolled in the database with electronic medical records available for review for at&#xD;
             least 12 months before the IUD insertion&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
        - Women with more than 50 years of age at the time of the IUD-insertion&#xD;
      </textblock>
    </criteria>
    <gender>Female</gender>
    <minimum_age>N/A</minimum_age>
    <maximum_age>50 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <location>
    <facility>
      <name>Kaiser Permanente Northern California</name>
      <address>
        <city>Oakland</city>
        <state>California</state>
        <zip>94612</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Kaiser Permanente Southern California</name>
      <address>
        <city>Pasadena</city>
        <state>California</state>
        <zip>91101</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Regenstrief Institute</name>
      <address>
        <city>Indianapolis</city>
        <state>Indiana</state>
        <zip>46202</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Kaiser Permanente Washington</name>
      <address>
        <city>Seattle</city>
        <state>Washington</state>
        <zip>98101</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <link>
    <url>http://clinicaltrials.bayer.com/</url>
    <description>Click here to find results for studies related to Bayer products</description>
  </link>
  <verification_date>November 2020</verification_date>
  <study_first_submitted>November 23, 2018</study_first_submitted>
  <study_first_submitted_qc>November 23, 2018</study_first_submitted_qc>
  <study_first_posted type="Actual">November 27, 2018</study_first_posted>
  <results_first_submitted>November 10, 2020</results_first_submitted>
  <results_first_submitted_qc>November 10, 2020</results_first_submitted_qc>
  <results_first_posted type="Actual">December 4, 2020</results_first_posted>
  <last_update_submitted>November 10, 2020</last_update_submitted>
  <last_update_submitted_qc>November 10, 2020</last_update_submitted_qc>
  <last_update_posted type="Actual">December 4, 2020</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <keyword>Contraception</keyword>
  <keyword>Breast-feeding</keyword>
  <keyword>Electronic medical records</keyword>
  <keyword>Uterine perforation</keyword>
  <keyword>Expulsion of intrauterine device</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Uterine Perforation</mesh_term>
  </condition_browse>
  <intervention_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Levonorgestrel</mesh_term>
  </intervention_browse>
  <provided_document_section>
    <provided_document>
      <document_type>Study Protocol</document_type>
      <document_has_protocol>Yes</document_has_protocol>
      <document_has_icf>No</document_has_icf>
      <document_has_sap>No</document_has_sap>
      <document_date>June 29, 2018</document_date>
      <document_url>https://ClinicalTrials.gov/ProvidedDocs/56/NCT03754556/Prot_000.pdf</document_url>
    </provided_document>
    <provided_document>
      <document_type>Statistical Analysis Plan</document_type>
      <document_has_protocol>No</document_has_protocol>
      <document_has_icf>No</document_has_icf>
      <document_has_sap>Yes</document_has_sap>
      <document_date>October 24, 2018</document_date>
      <document_url>https://ClinicalTrials.gov/ProvidedDocs/56/NCT03754556/SAP_001.pdf</document_url>
    </provided_document>
  </provided_document_section>

  <clinical_results>

    <participant_flow>
      <recruitment_details>This study was a retrospective cohort study, using the data from three health care systems: Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and one research institute with access to a health information exchange, Regenstrief Institute (RI)</recruitment_details>
      <pre_assignment_details>Between 01 January 2001 and 30 April 2018, 326658 participants were identified: 322898 participants with intrauterine device (IUD) type available and 94817 participants with breastfeeding status available (and IUD insertion within 12 months postpartum)</pre_assignment_details>
      <group_list>
        <group group_id="P1">
          <title>Women With IUD</title>
          <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
        </group>
      </group_list>
      <period_list>
        <period>
          <title>Overall Study</title>
          <milestone_list>
            <milestone>
              <title>STARTED</title>
              <participants_list>
                <participants group_id="P1" count="326658"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="326658"/>
              </participants_list>
            </milestone>
            <milestone>
              <title>NOT COMPLETED</title>
              <participants_list>
                <participants group_id="P1" count="0"/>
              </participants_list>
            </milestone>
          </milestone_list>
        </period>
      </period_list>
    </participant_flow>

    <baseline>
      <group_list>
        <group group_id="B1">
          <title>Women With IUD</title>
          <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
        </group>
      </group_list>
      <analyzed_list>
        <analyzed>
          <units>Participants</units>
          <scope>Overall</scope>
          <count_list>
            <count group_id="B1" value="326658"/>
          </count_list>
        </analyzed>
      </analyzed_list>
      <measure_list>
        <measure>
          <title>Age, Customized</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>≤ 28 years</title>
                  <measurement_list>
                    <measurement group_id="B1" value="119469"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt; 28 to ≤ 36 years</title>
                  <measurement_list>
                    <measurement group_id="B1" value="107871"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt; 36 to ≤ 50 years</title>
                  <measurement_list>
                    <measurement group_id="B1" value="99318"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Sex/Gender, Customized</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Female</title>
                  <measurement_list>
                    <measurement group_id="B1" value="326658"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Race/Ethnicity, Customized</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Asian/Pacific Islander</title>
                  <measurement_list>
                    <measurement group_id="B1" value="38911"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Hispanic black</title>
                  <measurement_list>
                    <measurement group_id="B1" value="696"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Hispanic white</title>
                  <measurement_list>
                    <measurement group_id="B1" value="42501"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Hispanic other</title>
                  <measurement_list>
                    <measurement group_id="B1" value="56180"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Non-Hispanic black</title>
                  <measurement_list>
                    <measurement group_id="B1" value="28323"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Non-Hispanic white</title>
                  <measurement_list>
                    <measurement group_id="B1" value="137102"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Other or multiple</title>
                  <measurement_list>
                    <measurement group_id="B1" value="16357"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Unknown</title>
                  <measurement_list>
                    <measurement group_id="B1" value="6588"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Breastfeeding status</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Yes (for those ≤ 52 weeks postpartum)</title>
                  <measurement_list>
                    <measurement group_id="B1" value="64186"/>
                  </measurement_list>
                </category>
                <category>
                  <title>No (for those ≤ 52 weeks postpartum)</title>
                  <measurement_list>
                    <measurement group_id="B1" value="30631"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Undetermined (for those ≤ 52 weeks postpartum)</title>
                  <measurement_list>
                    <measurement group_id="B1" value="3007"/>
                  </measurement_list>
                </category>
                <category>
                  <title>No delivery in the past year</title>
                  <measurement_list>
                    <measurement group_id="B1" value="228834"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Postpartum time of IUD insertion</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>0 to 3 days</title>
                  <measurement_list>
                    <measurement group_id="B1" value="2788"/>
                  </measurement_list>
                </category>
                <category>
                  <title>4 days to ≤ 6 weeks</title>
                  <measurement_list>
                    <measurement group_id="B1" value="17272"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt; 6 to ≤ 14 weeks</title>
                  <measurement_list>
                    <measurement group_id="B1" value="56047"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt; 14 to ≤ 52 weeks</title>
                  <measurement_list>
                    <measurement group_id="B1" value="21717"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt; 52 weeks or no delivery</title>
                  <measurement_list>
                    <measurement group_id="B1" value="228834"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>Menorrhagia</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>≤ 12 months before insertion</title>
                  <measurement_list>
                    <measurement group_id="B1" value="32552"/>
                  </measurement_list>
                </category>
                <category>
                  <title>&gt; 12 months or no diagnosis</title>
                  <measurement_list>
                    <measurement group_id="B1" value="294106"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
        <measure>
          <title>IUD type</title>
          <units>Participants</units>
          <param>Count of Participants</param>
          <class_list>
            <class>
              <category_list>
                <category>
                  <title>Levonorgestrel (LNG)-IUD</title>
                  <measurement_list>
                    <measurement group_id="B1" value="259234"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Copper IUD</title>
                  <measurement_list>
                    <measurement group_id="B1" value="63664"/>
                  </measurement_list>
                </category>
                <category>
                  <title>Unknown</title>
                  <measurement_list>
                    <measurement group_id="B1" value="3760"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </measure_list>
    </baseline>

    <outcome_list>
      <outcome>
        <type>Primary</type>
        <title>Crude Incidence Rate of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Breastfeeding</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.25" lower_limit="3.89" upper_limit="4.62"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.50" lower_limit="2.11" upper_limit="2.94"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Cumulative Incidence of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.60" lower_limit="0.54" upper_limit="0.67"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.35" lower_limit="0.29" upper_limit="0.43"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.61" lower_limit="1.43" upper_limit="1.81"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.88" lower_limit="0.71" upper_limit="1.08"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Hazard Ratio (HR) for Breastfeeding Status and Uterine Perforation-first Observed IUD Insertions</title>
        <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of uterine perforation among women who were not breastfeeding at the time of first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Breastfeeding Status and Uterine Perforation-first Observed IUD Insertions</title>
          <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of uterine perforation among women who were not breastfeeding at the time of first observed IUD insertion</description>
          <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
          <units>ajusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.37" lower_limit="1.12" upper_limit="1.66"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Crude Incidence Rate of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>≤ 6 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="5.14" lower_limit="4.44" upper_limit="5.92"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.77" lower_limit="3.42" upper_limit="4.15"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.24" lower_limit="1.80" upper_limit="2.75"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks postpartum or no delivery</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.68" lower_limit="0.61" upper_limit="0.76"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Cumulative Incidence of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>≤ 6 weeks postpartum (pp), 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.70" lower_limit="0.59" upper_limit="0.84"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks pp, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.54" lower_limit="0.48" upper_limit="0.61"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks pp, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.33" lower_limit="0.26" upper_limit="0.43"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks pp or no delivery, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.07" lower_limit="0.06" upper_limit="0.08"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>≤ 6 weeks pp, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.89" lower_limit="1.55" upper_limit="2.31"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks pp, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.42" lower_limit="1.25" upper_limit="1.61"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks pp, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.74" lower_limit="0.57" upper_limit="0.97"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks pp or no delivery, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.29" lower_limit="0.26" upper_limit="0.34"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Hazard Ratio (HR) for Postpartum Timing and Uterine Perforation-first Observed IUD Insertions</title>
        <description>Adjusted for propensity scores and breastfeeding status, to evaluate whether the risk of uterine perforation among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of uterine perforation among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt; 52 weeks postpartum</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Postpartum Timing and Uterine Perforation-first Observed IUD Insertions</title>
          <description>Adjusted for propensity scores and breastfeeding status, to evaluate whether the risk of uterine perforation among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of uterine perforation among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt; 52 weeks postpartum</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>ajusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>≤ 6 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="6.29" lower_limit="4.50" upper_limit="8.79"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.65" lower_limit="3.49" upper_limit="6.20"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.94" lower_limit="2.16" upper_limit="4.01"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and Uterine Perforation-first Observed IUD Insertions</title>
        <description>Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion &gt;14 weeks postpartum or with no recorded delivery</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and Uterine Perforation-first Observed IUD Insertions</title>
          <description>Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion &gt;14 weeks postpartum or with no recorded delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.44" lower_limit="2.70" upper_limit="4.40"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and Uterine Perforation-first Observed IUD Insertions</title>
        <description>Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion &gt; 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt;36 weeks postpartum or with no recorded delivery</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and Uterine Perforation-first Observed IUD Insertions</title>
          <description>Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion &gt; 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt;36 weeks postpartum or with no recorded delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.36" lower_limit="3.45" upper_limit="5.51"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Incidence Rate Ratio (IRR) for Uterine Perforation-first Observed IUD Insertions</title>
        <description>Adjusted for propensity score, overall and stratified by breastfeeding status at the time of IUD insertion for ≤ 36 weeks postpartum at IUD insertion versus &gt; 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up. Reference group: &gt; 36 weeks or no delivery</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Incidence Rate Ratio (IRR) for Uterine Perforation-first Observed IUD Insertions</title>
          <description>Adjusted for propensity score, overall and stratified by breastfeeding status at the time of IUD insertion for ≤ 36 weeks postpartum at IUD insertion versus &gt; 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up. Reference group: &gt; 36 weeks or no delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted incidence rate ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Overall, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.72" lower_limit="3.74" upper_limit="5.96"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Overall, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.10" lower_limit="3.43" upper_limit="4.90"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.11" lower_limit="0.57" upper_limit="2.47"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="6.61" lower_limit="5.03" upper_limit="8.76"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.47" lower_limit="0.80" upper_limit="3.07"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.86" lower_limit="4.00" upper_limit="5.93"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Incidence Rate Difference (IRD) for Uterine Perforation-first Observed IUD Insertions</title>
        <description>Propensity score-adjusted incidence rate differences (per 1,000 person-years) for uterine perforation for women ≤ 36 weeks postpartum at IUD insertion compared with those who were &gt; 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status. Reference group: &gt; 36 weeks or no delivery</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Incidence Rate Difference (IRD) for Uterine Perforation-first Observed IUD Insertions</title>
          <description>Propensity score-adjusted incidence rate differences (per 1,000 person-years) for uterine perforation for women ≤ 36 weeks postpartum at IUD insertion compared with those who were &gt; 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status. Reference group: &gt; 36 weeks or no delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Overall, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.75" lower_limit="3.05" upper_limit="4.45"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Overall, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.28" lower_limit="1.93" upper_limit="2.63"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.63" lower_limit="-3.39" upper_limit="4.64"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.92" lower_limit="3.22" upper_limit="4.63"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.38" lower_limit="-0.46" upper_limit="3.21"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.33" lower_limit="1.97" upper_limit="2.69"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Crude Incidence Rate of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259534"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.64" lower_limit="1.53" upper_limit="1.76"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.27" lower_limit="1.08" upper_limit="1.48"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Cumulative Incidence of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD, 1 year of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259234"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.22" lower_limit="0.20" upper_limit="0.24"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, 1 year of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.16" lower_limit="0.13" upper_limit="0.20"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD, 5 years of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259234"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.63" lower_limit="0.57" upper_limit="0.68"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, 5 years of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.55" lower_limit="0.44" upper_limit="0.68"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Hazard Ratio (HR) for IUD Type and Uterine Perforation-first Observed IUD Insertions</title>
        <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of uterine perforation among women with copper IUD at the time of first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for IUD Type and Uterine Perforation-first Observed IUD Insertions</title>
          <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of uterine perforation among women with copper IUD at the time of first observed IUD insertion</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.49" lower_limit="1.25" upper_limit="1.78"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Crude Incidence Rate of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) in the 12 months before IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) in the 12 months before IUD insertion</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Yes</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.00" lower_limit="0.77" upper_limit="1.28"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>No</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="294106"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.63" lower_limit="1.53" upper_limit="1.74"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Cumulative Incidence of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) in the 12 months before IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) in the 12 months before IUD insertion</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Yes, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.10" lower_limit="0.07" upper_limit="0.14"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>No, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="294106"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.22" lower_limit="0.20" upper_limit="0.24"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Yes, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.41" lower_limit="0.31" upper_limit="0.56"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>No, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.63" lower_limit="0.58" upper_limit="0.69"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Adjusted Hazard Ratio (HR) for Menorrhagia Status and Uterine Perforation-first Observed IUD Insertions</title>
        <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of uterine perforation among women who do not have this indication</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) in the 12 months before IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Menorrhagia Status and Uterine Perforation-first Observed IUD Insertions</title>
          <description>Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of uterine perforation among women who do not have this indication</description>
          <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) in the 12 months before IUD insertion</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.38" lower_limit="1.01" upper_limit="1.88"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Effect Modification of Breastfeeding Status on Postpartum Timing for Uterine Perforation</title>
        <description>Propensity score-adjusted hazard ratios to evaluate the extent to which breastfeeding status (yes vs. no) modified the association of uterine perforation for women with IUD insertion at different time periods postpartum (i.e., IUD insertion ≤ 14 weeks versus IUD insertion &gt; 14 weeks postpartum) among women with a recorded delivery within the past 52 weeks at the time of the first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Effect Modification of Breastfeeding Status on Postpartum Timing for Uterine Perforation</title>
          <description>Propensity score-adjusted hazard ratios to evaluate the extent to which breastfeeding status (yes vs. no) modified the association of uterine perforation for women with IUD insertion at different time periods postpartum (i.e., IUD insertion ≤ 14 weeks versus IUD insertion &gt; 14 weeks postpartum) among women with a recorded delivery within the past 52 weeks at the time of the first observed IUD insertion</description>
          <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>≤ 14 weeks, breastfeeding yes vs.no</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="94817"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.28" lower_limit="1.02" upper_limit="1.61"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 to ≤ 52 weeks, breastfeeding yes vs.no</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="94817"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.41" lower_limit="1.47" upper_limit="3.95"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding yes, ≤ 14 vs. &gt; 14 to ≤ 52 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.36" lower_limit="1.01" upper_limit="1.83"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding no, ≤ 14 vs. &gt; 14 to ≤ 52 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.56" lower_limit="1.62" upper_limit="4.02"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Effect Modification of IUD Type on Breastfeeding Status for Uterine Perforation</title>
        <description>Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Effect Modification of IUD Type on Breastfeeding Status for Uterine Perforation</title>
          <description>Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion</description>
          <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94205"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD, breastfeeding yes vs.no</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="72201"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.33" lower_limit="1.07" upper_limit="1.64"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, breastfeeding yes vs.no</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="22004"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.66" lower_limit="0.94" upper_limit="2.94"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Primary</type>
        <title>Effect Modification of IUD Type on Postpartum Timing for Uterine Perforation</title>
        <description>Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, &gt; 6 and ≤ 14 weeks, &gt; 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, &gt; 52 weeks or no delivery</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Effect Modification of IUD Type on Postpartum Timing for Uterine Perforation</title>
          <description>Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, &gt; 6 and ≤ 14 weeks, &gt; 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, &gt; 52 weeks or no delivery</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD, ≤ 6 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="15631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="6.78" lower_limit="4.74" upper_limit="9.70"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD, &gt; 6 to ≤ 14 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="42760"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="5.11" lower_limit="3.75" upper_limit="6.95"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD, &gt; 14 to ≤ 52 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="16110"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.13" lower_limit="2.21" upper_limit="4.42"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, ≤ 6 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="4228"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.30" lower_limit="2.38" upper_limit="7.75"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, &gt; 6 to ≤ 14 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="12934"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.61" lower_limit="1.56" upper_limit="4.36"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, &gt; 14 to ≤ 52 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="5379"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.01" lower_limit="1.05" upper_limit="3.85"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Crude Incidence Rate of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Breastfeeding</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="10.23" lower_limit="9.68" upper_limit="10.81"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="14.58" lower_limit="13.62" upper_limit="15.59"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Cumulative Incidence of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women who were within 52 weeks postpartum and were or were not breastfeeding at the time of IUD insertion</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.55" lower_limit="1.44" upper_limit="1.65"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.45" lower_limit="2.27" upper_limit="2.65"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.49" lower_limit="3.25" upper_limit="3.73"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.57" lower_limit="4.22" upper_limit="4.95"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Hazard Ratio (HR) for Breastfeeding Status and IUD Expulsion-first Observed IUD Insertions</title>
        <description>Propensity score-adjusted to evaluate whether the risk of IUD expulsion among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of IUD expulsion among women who were not breastfeeding at the time of first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Breastfeeding Status and IUD Expulsion-first Observed IUD Insertions</title>
          <description>Propensity score-adjusted to evaluate whether the risk of IUD expulsion among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of IUD expulsion among women who were not breastfeeding at the time of first observed IUD insertion</description>
          <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94817"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.71" lower_limit="0.64" upper_limit="0.78"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Crude Incidence Rate of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>≤ 3 days</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="2788"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="46.54" lower_limit="40.54" upper_limit="53.18"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>4 days to ≤ 6 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="17272"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="10.88" lower_limit="9.78" upper_limit="12.08"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>≤ 6 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="15.33" lower_limit="14.10" upper_limit="16.65"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="9.29" lower_limit="8.73" upper_limit="9.87"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="14.36" lower_limit="13.22" upper_limit="15.57"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks postpartum or no delivery</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="14.93" lower_limit="14.57" upper_limit="15.29"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Cumulative Incidence of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>≤ 3 days, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="2788"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="7.84" lower_limit="6.83" upper_limit="9.00"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>4 days to ≤ 6 weeks, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="17272"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.87" lower_limit="3.40" upper_limit="4.42"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>≤ 6 weeks postpartum (pp), 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.46" lower_limit="2.24" upper_limit="2.71"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks pp, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.40" lower_limit="1.30" upper_limit="1.51"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks pp, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.33" lower_limit="2.12" upper_limit="2.56"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks pp or no delivery, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.49" lower_limit="2.42" upper_limit="2.56"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>≤ 3 days, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="2788"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="10.73" lower_limit="9.12" upper_limit="12.61"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>4 days to ≤ 6 weeks, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="17272"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.61" lower_limit="1.42" upper_limit="1.84"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>≤ 6 weeks pp, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.81" lower_limit="4.33" upper_limit="5.33"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks pp, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.18" lower_limit="2.95" upper_limit="3.42"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks pp, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.55" lower_limit="4.12" upper_limit="5.02"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks pp or no delivery, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.88" lower_limit="4.74" upper_limit="5.02"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Hazard Ratio (HR) for Postpartum Timing and IUD Expulsion-first Observed IUD Insertions</title>
        <description>Adjusted for propensity score and breastfeeding status, to evaluate whether the risk of IUD expulsion before and after 49 days of insertion among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of IUD expulsion among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks Reference group: IUD insertion &gt; 52 weeks postpartum</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Postpartum Timing and IUD Expulsion-first Observed IUD Insertions</title>
          <description>Adjusted for propensity score and breastfeeding status, to evaluate whether the risk of IUD expulsion before and after 49 days of insertion among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of IUD expulsion among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks Reference group: IUD insertion &gt; 52 weeks postpartum</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Within 49 days, ≤ 6 weeks postpartum (pp)</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.93" lower_limit="1.59" upper_limit="2.35"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Within 49 days, &gt; 6 weeks and ≤ 14 weeks pp</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.88" lower_limit="0.74" upper_limit="1.05"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Within 49 days, &gt; 14 weeks and ≤ 52 weeks pp</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.38" lower_limit="1.14" upper_limit="1.68"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>After 49 days, ≤ 6 weeks pp</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.32" lower_limit="1.15" upper_limit="1.53"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>After 49 days, &gt; 6 weeks and ≤ 14 weeks pp</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.03" lower_limit="0.92" upper_limit="1.16"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>After 49 days, &gt; 14 weeks and ≤ 52 weeks pp</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.39" lower_limit="1.23" upper_limit="1.57"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and IUD Expulsion-first Observed IUD Insertions</title>
        <description>Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion &gt;14 weeks postpartum or with no recorded delivery</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and IUD Expulsion-first Observed IUD Insertions</title>
          <description>Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion &gt;14 weeks postpartum or with no recorded delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.88" lower_limit="0.83" upper_limit="0.94"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and IUD Expulsion-first Observed IUD Insertions</title>
        <description>Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion &gt; 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt;36 weeks postpartum or with no recorded delivery</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and IUD Expulsion-first Observed IUD Insertions</title>
          <description>Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion &gt; 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion &gt;36 weeks postpartum or with no recorded delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.95" lower_limit="0.89" upper_limit="1.00"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Incidence Rate Ratio (IRR) for IUD Expulsion-first Observed IUD Insertions</title>
        <description>Overall and stratified by breastfeeding status at the time of IUD insertion for IUD expulsion for ≤ 36 weeks postpartum at IUD insertion versus &gt; 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up Reference group: &gt; 36 weeks or no delivery</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Incidence Rate Ratio (IRR) for IUD Expulsion-first Observed IUD Insertions</title>
          <description>Overall and stratified by breastfeeding status at the time of IUD insertion for IUD expulsion for ≤ 36 weeks postpartum at IUD insertion versus &gt; 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up Reference group: &gt; 36 weeks or no delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>adjusted incidence rate ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Overall, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.21" lower_limit="1.12" upper_limit="1.30"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Overall, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.20" lower_limit="1.13" upper_limit="1.28"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.60" lower_limit="0.44" upper_limit="0.85"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.25" lower_limit="1.16" upper_limit="1.35"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.80" lower_limit="0.59" upper_limit="1.10"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.23" lower_limit="1.15" upper_limit="1.31"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Incidence Rate Difference (IRD) for IUD Expulsion-first Observed IUD Insertions</title>
        <description>Adjusted incidence rate differences (per 1,000 person-years) for IUD expulsion for women ≤ 36 weeks postpartum at IUD insertion compared with those who were &gt; 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status Reference group: &gt; 36 weeks or no delivery</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Incidence Rate Difference (IRD) for IUD Expulsion-first Observed IUD Insertions</title>
          <description>Adjusted incidence rate differences (per 1,000 person-years) for IUD expulsion for women ≤ 36 weeks postpartum at IUD insertion compared with those who were &gt; 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status Reference group: &gt; 36 weeks or no delivery</description>
          <population>Women with first observed IUD insertions at different postpartum timing or women without recorded delivery within the past 52 weeks</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Overall, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.28" lower_limit="2.50" upper_limit="6.06"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Overall, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.37" lower_limit="1.53" upper_limit="3.22"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="-10.79" lower_limit="-19.43" upper_limit="-2.15"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="-2.62" lower_limit="-6.51" upper_limit="1.26"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="5.11" lower_limit="3.27" upper_limit="6.94"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.65" lower_limit="1.78" upper_limit="3.53"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Crude Incidence Rate of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259534"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="13.95" lower_limit="13.63" upper_limit="14.28"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="14.08" lower_limit="13.44" upper_limit="14.75"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Cumulative Incidence of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD, 1 year of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259234"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.30" lower_limit="2.24" upper_limit="2.36"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, 1 year of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.30" lower_limit="2.18" upper_limit="2.44"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD, 5 years of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259234"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.52" lower_limit="4.40" upper_limit="4.65"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, 5 years of follow up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4.82" lower_limit="4.56" upper_limit="5.10"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Hazard Ratio (HR) for IUD Type and IUD Expulsion-first Observed IUD Insertions</title>
        <description>Propensity score adjusted to evaluate whether the risk of IUD expulsion among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of IUD expulsion among women with copper IUD at the time of first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for IUD Type and IUD Expulsion-first Observed IUD Insertions</title>
          <description>Propensity score adjusted to evaluate whether the risk of IUD expulsion among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of IUD expulsion among women with copper IUD at the time of first observed IUD insertion</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.69" lower_limit="0.65" upper_limit="0.73"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Crude Incidence Rate of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
        <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) available in the 12 months before IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Crude Incidence Rate of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
          <description>Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)</description>
          <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) available in the 12 months before IUD insertion</population>
          <units>per 1000 person-years</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Yes</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="39.56" lower_limit="38.03" upper_limit="41.13"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>No</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="294106"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="11.10" lower_limit="10.83" upper_limit="11.38"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Cumulative Incidence of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
        <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
        <time_frame>At 1 year and 5 years of follow-up</time_frame>
        <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) available in the 12 months before IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Cumulative Incidence of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions</title>
          <description>Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions</description>
          <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) available in the 12 months before IUD insertion</population>
          <units>number of outcomes/IUD insertions (%)</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Yes, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="6.89" lower_limit="6.60" upper_limit="7.20"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>No, 1 year of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="294106"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.78" lower_limit="1.73" upper_limit="1.84"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Yes, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="11.89" lower_limit="11.40" upper_limit="12.41"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>No, 5 years of follow-up</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="294106"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3.72" lower_limit="3.61" upper_limit="3.83"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Adjusted Hazard Ratio (HR) for Menorrhagia Status and IUD Expulsion-first Observed IUD Insertions</title>
        <description>Propensity score adjusted to evaluate whether the risk of IUD expulsion among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of IUD expulsion among women who do not have this indication</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) available in the 12 months before IUD insertion</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Adjusted Hazard Ratio (HR) for Menorrhagia Status and IUD Expulsion-first Observed IUD Insertions</title>
          <description>Propensity score adjusted to evaluate whether the risk of IUD expulsion among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of IUD expulsion among women who do not have this indication</description>
          <population>Women with menorrhagia (heavy menstrual bleeding) status (yes/no) available in the 12 months before IUD insertion</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="2.79" lower_limit="2.62" upper_limit="2.98"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Effect Modification of IUD Type on Breastfeeding Status for IUD Expulsion</title>
        <description>Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Effect Modification of IUD Type on Breastfeeding Status for IUD Expulsion</title>
          <description>Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion</description>
          <population>Women who had given birth in the previous 52 weeks and had breastfeeding status &quot;yes&quot; or &quot;no&quot; were included in this analysis</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="94205"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD, breastfeeding yes vs.no</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="72201"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.72" lower_limit="0.64" upper_limit="0.80"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, breastfeeding yes vs.no</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="22004"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.66" lower_limit="0.54" upper_limit="0.80"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Effect Modification of IUD Type on Postpartum Timing for IUD Expulsion</title>
        <description>Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, &gt; 6 and ≤ 14 weeks, &gt; 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, &gt; 52 weeks or no delivery</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Effect Modification of IUD Type on Postpartum Timing for IUD Expulsion</title>
          <description>Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, &gt; 6 and ≤ 14 weeks, &gt; 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, &gt; 52 weeks or no delivery</description>
          <population>Women with either LNG-IUD (levonorgestrel-releasing intrauterine system) or copper IUD insertions</population>
          <units>adjusted hazard ratio</units>
          <param>Number</param>
          <dispersion>95% Confidence Interval</dispersion>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="322898"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>LNG-IUD, ≤ 6 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="15631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.59" lower_limit="1.38" upper_limit="1.82"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD, &gt; 6 to ≤ 14 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="42760"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.01" lower_limit="0.90" upper_limit="1.14"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD, &gt; 14 to ≤ 52 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="16110"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.40" lower_limit="1.23" upper_limit="1.58"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, ≤ 6 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="4228"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.23" lower_limit="0.98" upper_limit="1.53"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, &gt; 6 to ≤ 14 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="12934"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="0.96" lower_limit="0.81" upper_limit="1.13"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD, &gt; 14 to ≤ 52 weeks</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="5379"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1.35" lower_limit="1.13" upper_limit="1.63"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Number of Indicators of a Potentially Difficult Insertion, Overall, by Breastfeeding Status, and by Postpartum Timing of IUD Insertion-first Observed IUD Insertions</title>
        <description>To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Number of Indicators of a Potentially Difficult Insertion, Overall, by Breastfeeding Status, and by Postpartum Timing of IUD Insertion-first Observed IUD Insertions</title>
          <description>To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)</description>
          <population>Women with first observed IUD insertions</population>
          <units>indicators</units>
          <param>Number</param>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Overall</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="29777"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Breastfeeding</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="64186"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1686"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Not breastfeeding</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="30631"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1077"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>≤ 6 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="20060"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="573"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 6 weeks and ≤ 14 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="56047"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1261"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 14 weeks and ≤ 52 weeks postpartum</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="21717"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="1146"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>&gt; 52 weeks postpartum or no delivery</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="228834"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="26797"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
      <outcome>
        <type>Secondary</type>
        <title>Number of Indicators of a Potentially Difficult Insertion, Overall, by IUD Type and by Menorrhagia Status-first Observed IUD Insertions</title>
        <description>To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)</description>
        <time_frame>Up to 11 years</time_frame>
        <population>Women with first observed IUD insertions</population>
        <group_list>
          <group group_id="O1">
            <title>Women With IUD</title>
            <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
          </group>
        </group_list>
        <measure>
          <title>Number of Indicators of a Potentially Difficult Insertion, Overall, by IUD Type and by Menorrhagia Status-first Observed IUD Insertions</title>
          <description>To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)</description>
          <population>Women with first observed IUD insertions</population>
          <units>indicators</units>
          <param>Number</param>
          <analyzed_list>
            <analyzed>
              <units>Participants</units>
              <scope>Measure</scope>
              <count_list>
                <count group_id="O1" value="326658"/>
              </count_list>
            </analyzed>
          </analyzed_list>
          <class_list>
            <class>
              <title>Overall</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="326658"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="29777"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>LNG-IUD</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="259234"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="24666"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Copper IUD</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="63664"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="4648"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>With menorrhagia in the past year</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="32552"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="3754"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
            <class>
              <title>Without menorrhagia in the past year</title>
              <analyzed_list>
                <analyzed>
                  <units>Participants</units>
                  <scope>Class</scope>
                  <count_list>
                    <count group_id="O1" value="294106"/>
                  </count_list>
                </analyzed>
              </analyzed_list>
              <category_list>
                <category>
                  <measurement_list>
                    <measurement group_id="O1" value="26023"/>
                  </measurement_list>
                </category>
              </category_list>
            </class>
          </class_list>
        </measure>
      </outcome>
    </outcome_list>

    <reported_events>
      <time_frame>Retrospective analysis of data from 2001 to 2018</time_frame>
      <desc>This research study used secondary data from which personal identifiers were removed. The outcomes of uterine perforation and IUD expulsion are reported in the study results. Based on current guidelines from ISPE and the EMA, non-interventional studies conducted using electronic claims and health care records do not require reporting of adverse events or reactions</desc>
      <group_list>
        <group group_id="E1">
          <title>Women With IUD</title>
          <description>Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.</description>
        </group>
      </group_list>
      <serious_events>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, all-cause mortality</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="0"/>
              </event>
              <event>
                <sub_title>Total, serious adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="0"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </serious_events>
      <other_events>
        <frequency_threshold>0</frequency_threshold>
        <category_list>
          <category>
            <title>Total</title>
            <event_list>
              <event>
                <sub_title>Total, other adverse events</sub_title>
                <counts group_id="E1" subjects_affected="0" subjects_at_risk="0"/>
              </event>
            </event_list>
          </category>
        </category_list>
      </other_events>
    </reported_events>

    <certain_agreements>
      <pi_employee>Principal Investigators are NOT employed by the organization sponsoring the study.</pi_employee>
      <restrictive_agreement>PI shall ensure that a written manuscript of any intended publication will be provided to BAYER at least 30 days prior to the intended submission or presentation in order to allow BAYER to review it. PI further agrees, upon written request from BAYER, not to submit such abstract or manuscript for publication or to make such presentation for the reasonably required time in order to allow for actions to be taken, which are necessary for BAYER to preserve rights to patents.</restrictive_agreement>
    </certain_agreements>
    <point_of_contact>
      <name_or_title>Therapeutic Area Head</name_or_title>
      <organization>Bayer AG</organization>
      <phone>(+) 1-888-8422937</phone>
      <email>clinical-trials-contact@bayer.com</email>
    </point_of_contact>
  </clinical_results>
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03754556
org study id: 19682
nct id: NCT03754556
lead sponsor: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
Study to analyze electronic medical records of women using an intrauterine device (IUD). The
      study was required by the FDA for the marketed IUD Mirena (US Post-marketing requirement;
      short name of study: APEX IUD).

      The study analyzed the risks that the IUD was expelled or perforated the womb for the
      following group comparisons:

        -  Women who were breastfeeding at the time of IUD insertion and within 52 weeks postpartum
           versus women who were not breastfeeding at the time of IUD insertion and within 52 weeks
           postpartum.

        -  Women who had a first observed IUD insertion within different time periods after
           childbirth (i.e., ≤ 6 weeks, > 6 weeks and ≤ 14 weeks, > 14 weeks and ≤ 52 weeks) versus
           women who had their first observed IUD insertion more than 52 weeks after childbirth,
           including women without a recorded delivery within the past 52 weeks. An additional
           analysis involved 5-level postpartum timing (i.e., 0 to 3 days, 4 days to ≤ 6 weeks, > 6
           weeks to ≤ 14 weeks, > 14 weeks to ≤ 52 weeks) versus the > 52 week postpartum group.

      The study also analyzed the risks that the IUD was expelled or perforated the womb for
      different types of IUDs. In addition, the study aimed to assess the following interactions:

        -  The extent to which the type of IUD (IUDs releasing the hormone LNG versus Copper IUDs)
           modified the risk that an IUD was expelled or perforated the womb in relation to
           breastfeeding and/ or in relation to the point in time when the IUD was inserted after
           childbirth.

        -  The extent to which the breastfeeding status modified the risk that an IUD was expelled
           or perforated the womb in relation to the point in time when the IUD was inserted after
           childbirth.
observational model: Cohort
time perspective: Retrospective
measure: Crude Incidence Rate of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of Uterine Perforation Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for Breastfeeding Status and Uterine Perforation-first Observed IUD Insertions
time frame: Up to 11 years
description: Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of uterine perforation among women who were not breastfeeding at the time of first observed IUD insertion
measure: Crude Incidence Rate of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of Uterine Perforation Categorized by Postpartum Timing-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for Postpartum Timing and Uterine Perforation-first Observed IUD Insertions
time frame: Up to 11 years
description: Adjusted for propensity scores and breastfeeding status, to evaluate whether the risk of uterine perforation among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of uterine perforation among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks. Reference group: IUD insertion > 52 weeks postpartum
measure: Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and Uterine Perforation-first Observed IUD Insertions
time frame: Up to 11 years
description: Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion >14 weeks postpartum or with no recorded delivery
measure: Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and Uterine Perforation-first Observed IUD Insertions
time frame: Up to 11 years
description: Adjusted for propensity scores and breastfeeding status, to estimate the risk of uterine perforation among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion > 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion >36 weeks postpartum or with no recorded delivery
measure: Adjusted Incidence Rate Ratio (IRR) for Uterine Perforation-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Adjusted for propensity score, overall and stratified by breastfeeding status at the time of IUD insertion for ≤ 36 weeks postpartum at IUD insertion versus > 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up. Reference group: > 36 weeks or no delivery
measure: Adjusted Incidence Rate Difference (IRD) for Uterine Perforation-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Propensity score-adjusted incidence rate differences (per 1,000 person-years) for uterine perforation for women ≤ 36 weeks postpartum at IUD insertion compared with those who were > 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status. Reference group: > 36 weeks or no delivery
measure: Crude Incidence Rate of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of Uterine Perforation Stratified by IUD Type-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for IUD Type and Uterine Perforation-first Observed IUD Insertions
time frame: Up to 11 years
description: Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of uterine perforation among women with copper IUD at the time of first observed IUD insertion
measure: Crude Incidence Rate of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of Uterine Perforation Stratified by Menorrhagia Status-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for Menorrhagia Status and Uterine Perforation-first Observed IUD Insertions
time frame: Up to 11 years
description: Propensity score-adjusted hazard ratio to evaluate whether the risk of uterine perforation among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of uterine perforation among women who do not have this indication
measure: Effect Modification of Breastfeeding Status on Postpartum Timing for Uterine Perforation
time frame: Up to 11 years
description: Propensity score-adjusted hazard ratios to evaluate the extent to which breastfeeding status (yes vs. no) modified the association of uterine perforation for women with IUD insertion at different time periods postpartum (i.e., IUD insertion ≤ 14 weeks versus IUD insertion > 14 weeks postpartum) among women with a recorded delivery within the past 52 weeks at the time of the first observed IUD insertion
measure: Effect Modification of IUD Type on Breastfeeding Status for Uterine Perforation
time frame: Up to 11 years
description: Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion
measure: Effect Modification of IUD Type on Postpartum Timing for Uterine Perforation
time frame: Up to 11 years
description: Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between uterine perforation and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, > 6 and ≤ 14 weeks, > 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, > 52 weeks or no delivery
measure: Crude Incidence Rate of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of IUD Expulsion Stratified by Breastfeeding Status Among Women Within 52 Weeks Postpartum-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for Breastfeeding Status and IUD Expulsion-first Observed IUD Insertions
time frame: Up to 11 years
description: Propensity score-adjusted to evaluate whether the risk of IUD expulsion among women who were breastfeeding at the time of first observed IUD insertion differs from the risk of IUD expulsion among women who were not breastfeeding at the time of first observed IUD insertion
measure: Crude Incidence Rate of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of IUD Expulsion Categorized by Postpartum Timing-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for Postpartum Timing and IUD Expulsion-first Observed IUD Insertions
time frame: Up to 11 years
description: Adjusted for propensity score and breastfeeding status, to evaluate whether the risk of IUD expulsion before and after 49 days of insertion among women who had a first observed IUD insertion within different time periods postpartum differs from the risk of IUD expulsion among women who had their first observed IUD insertion more than 52 weeks postpartum, including women without a recorded delivery within the past 52 weeks Reference group: IUD insertion > 52 weeks postpartum
measure: Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 14-week Cut Point and IUD Expulsion-first Observed IUD Insertions
time frame: Up to 11 years
description: Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion early in the postpartum period (i.e., up to 14 weeks postpartum) versus those who had a first observed IUD insertion late in the postpartum period (i.e., more than 14 weeks postpartum, including women without recorded delivery within the past 52 weeks). Reference group: IUD insertion >14 weeks postpartum or with no recorded delivery
measure: Adjusted Hazard Ratio (HR) for Postpartum Timing Risk 36-week Cut Point and IUD Expulsion-first Observed IUD Insertions
time frame: Up to 11 years
description: Adjusted for propensity scores, to estimate the risk of IUD expulsion among women who had a first observed IUD insertion ≤ 36 weeks postpartum versus women who had a first observed IUD insertion > 36 weeks postpartum, including women without recorded delivery within the past 52 weeks. Reference group: IUD insertion >36 weeks postpartum or with no recorded delivery
measure: Adjusted Incidence Rate Ratio (IRR) for IUD Expulsion-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Overall and stratified by breastfeeding status at the time of IUD insertion for IUD expulsion for ≤ 36 weeks postpartum at IUD insertion versus > 36 weeks postpartum or with no recorded delivery, at 1 year and 5 years of follow-up Reference group: > 36 weeks or no delivery
measure: Adjusted Incidence Rate Difference (IRD) for IUD Expulsion-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Adjusted incidence rate differences (per 1,000 person-years) for IUD expulsion for women ≤ 36 weeks postpartum at IUD insertion compared with those who were > 36 weeks postpartum or with no recorded delivery, 1 year of follow-up and 5 years of follow-up, overall and stratified by breastfeeding status Reference group: > 36 weeks or no delivery
measure: Crude Incidence Rate of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of IUD Expulsion Stratified by IUD Type-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for IUD Type and IUD Expulsion-first Observed IUD Insertions
time frame: Up to 11 years
description: Propensity score adjusted to evaluate whether the risk of IUD expulsion among women with LNG-releasing IUD at the time of first observed IUD insertion differs from the risk of IUD expulsion among women with copper IUD at the time of first observed IUD insertion
measure: Crude Incidence Rate of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions
time frame: Up to 11 years
description: Crude incidence rate was calculated as the number of outcomes occurring during the person-time at risk divided by the total person-time at risk (in person-years)
measure: Cumulative Incidence of IUD Expulsion Stratified by Menorrhagia Status-first Observed IUD Insertions
time frame: At 1 year and 5 years of follow-up
description: Crude estimates of the cumulative incidence, defined as number of outcomes occurring up to a time point out of the number of IUD insertions
measure: Adjusted Hazard Ratio (HR) for Menorrhagia Status and IUD Expulsion-first Observed IUD Insertions
time frame: Up to 11 years
description: Propensity score adjusted to evaluate whether the risk of IUD expulsion among women using an IUD who have at least one diagnosis code indicating menorrhagia in the 12 months before IUD insertion differs from the risk of IUD expulsion among women who do not have this indication
measure: Effect Modification of IUD Type on Breastfeeding Status for IUD Expulsion
time frame: Up to 11 years
description: Propensity score-adjusted hazard ratios to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and breastfeeding among women who were and were not breastfeeding at the time of first observed IUD insertion
measure: Effect Modification of IUD Type on Postpartum Timing for IUD Expulsion
time frame: Up to 11 years
description: Adjusted for propensity score and breastfeeding status, to evaluate the extent to which type of IUD (LNG-IUD vs. copper IUD) modified the association between IUD expulsion and postpartum timing of IUD insertion for women with IUD insertion at different time periods postpartum (i.e., ≤ 6 weeks, > 6 and ≤ 14 weeks, > 14 and ≤ 52 weeks) versus IUD insertion more than 52 weeks postpartum, including no recorded delivery within the past 52 weeks, at the time of the first observed IUD insertion. Reference group: LNG-IUD or Copper IUD, > 52 weeks or no delivery
measure: Number of Indicators of a Potentially Difficult Insertion, Overall, by Breastfeeding Status, and by Postpartum Timing of IUD Insertion-first Observed IUD Insertions
time frame: Up to 11 years
description: To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)
measure: Number of Indicators of a Potentially Difficult Insertion, Overall, by IUD Type and by Menorrhagia Status-first Observed IUD Insertions
time frame: Up to 11 years
description: To describe the prevalence of indicators of a difficult IUD insertion (e.g., need for cervical dilation, ultrasound guidance, paracervical block, clinician not indicating difficulty, use of misoprostol among all users)
arm group label: Women with IUD
description: Women with an intrauterine device (IUD) and electronic health records in the Kaiser Permanente Northern California (KPNC), Kaiser Permanente Southern California (KPSC), Kaiser Permanente Washington (KPWA) and the Regenstrief Institute (RI) databases.
intervention type: Device
intervention name: Intrauterine device
description: Intrauterine devices, e.g. BAY86-5028 (Mirena, Skyla, Kyleena), Liletta and ParaGard
arm group label: Women with IUD
other name: Levonorgestrel, Copper IUD
study pop: 
sampling method: Non-Probability Sample
criteria: 
gender: Female
minimum age: N/A
maximum age: 50 Years
healthy volunteers: Accepts Healthy Volunteers
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country: United States
url: http://clinicaltrials.bayer.com/
description: Click here to find results for studies related to Bayer products
responsible party type: Sponsor
mesh term: Uterine Perforation
mesh term: Levonorgestrel
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