Expulsion of intrauterine devices after postpartum placement by timing of placement, delivery type, and intrauterine device type: a systematic review and meta-analysis.
OBJECTIVES
To provide updated and more detailed pooled intrauterine device expulsion rates and expulsion risk estimates among women with postpartum intrauterine device placement by timing of insertion, delivery type, and intrauterine device type to inform current intrauterine device insertion practices in the United States.


DATA SOURCES
We searched PubMed, Cochrane Library, and ClinicalTrials.gov through June 2019.


STUDY ELIGIBILITY CRITERIA
We included all studies, of any study design, that examined postpartum placement of Copper T380A (copper) or levonorgestrel-containing intrauterine devices that reported counts of expulsion.


STUDY APPRAISAL AND SYNTHESIS METHODS
We evaluated intrauterine device expulsion among women receiving postpartum intrauterine devices in the "immediate" (within 10 minutes), "early inpatient" (>10 minutes to <72 hours), "early outpatient" (72 hours to <4 weeks), and interval (≥4 weeks) time periods after delivery. We assessed study quality using the US Preventive Services Task Force evidence grading system. We calculated pooled absolute rates of partial and complete intrauterine device expulsion separately and estimated adjusted relative risks by the timing of postpartum placement, delivery type, and intrauterine device type using log-binomial multivariable regression.


RESULTS
We identified 48 level I to II-3 studies of poor to good quality that reported a total of 7661 intrauterine device placements. Complete intrauterine device expulsion rates varied by timing of placement as follows: 10.2% (range, 0.0-26.7) for immediate; 13.2% (3.5-46.7) for early inpatient; 0% for early outpatient; and 1.8% (0.0-4.8) for interval placements. Complete intrauterine device expulsion rates also varied by delivery type: 14.8% (range, 4.8-43.1) for vaginal and 3.8% (0.0-21.1) for cesarean deliveries. Among immediate postpartum vaginal placements, the expulsion rate for levonorgetrel intrauterine devices was 27.4% (range, 18.8-45.2) and 12.4% (4.8-43.1) for copper intrauterine devices. Compared with interval placement, immediate and early postpartum placements (inpatient and outpatient combined) were associated with greater risk of complete expulsion (adjusted risk ratio, 8.33; 95% confidence interval, 4.32-16.08, and adjusted risk ratio, 5.27; 95% confidence interval, 2.56-10.85, respectively). Among immediate postpartum placements, risk of expulsion was greater for placement after vaginal compared with cesarean deliveries (adjusted risk ratio, 4.57; 95% confidence interval, 3.49-5.99). Among immediate placements at the time of vaginal delivery, levonorgestrel intrauterine devices were associated with a greater risk of expulsion compared with copper intrauterine devices (adjusted risk ratio, 1.90; 95% confidence interval, 1.36-2.65).


CONCLUSION
Although intrauterine device expulsion rates vary by timing of placement, type, and mode of delivery, intrauterine device insertion can take place at any time. Understanding the risk of intrauterine device expulsion at each time period will enable women to make an informed choice about when to initiate use of an intrauterine device in the postpartum period based on their own goals and preferences.