***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: People with sickle cell disease have a chronically activated coagulation system and display hemostatic perturbations , but it is unknown whether they experience an increased risk of venous thromboembolism . We conducted a case-control study of venous thromboembolism that included 515 hospitalized black patients and 555 black controls obtained from medical clinics . All subjects were assayed for hemoglobin S and hemoglobin C genotypes . The prevalence of the S allele was 0.070 and 0.032 for case patients and controls , respectively ( P < .001 ) . The odds that a patient had sickle cell trait were approximately twice that of a control , indicating that the risk of venous thromboembolism is increased approximately 2-fold among blacks with sickle cell trait compared with those with the wild-type genotype ( odds ratio = 1.8 with 95 % confidence interval , 1.2 - 2.9 ) . The odds ratio for pulmonary embolism and sickle cell trait was higher , 3.9 ( 2.2 - 6.9 ) . The prevalence of sickle cell disease was also increased among case patients compared with controls . We conclude that sickle cell trait is a risk factor for venous thromboembolism and that the proportion of venous thromboembolism among blacks attributable to the mutation is approximately 7 % OBJECTIVE Our purpose was to determine the rate of preeclampsia in women who are positive for sickle cell trait . STUDY DESIGN All African-American women were tested for sickle cell trait with the " sickledex " screen at the fist prenatal visit and prospect ively enrolled in this study from March 1994 to June 1995 .  " Sickledex " screens were confirmed with hemoglobin electrophoresis . Demographic data were collected at the time of enrollment . Outcome data , including preeclampsia ( as defined by The American College of Obstetricians and Gynecologists criteria ) , gestational age at delivery , birth weight , and postpartum endometritis were collected immediately post partum . Assuming a 10 % rate of positive sickle cell trait , 1100 patients were required to demonstrate a doubling in the rate of preeclampsia with 80 % power and p < 0.05 . The Student t  test , the  Mann-Whitney U  test , chi 2 analysis , and Fisher 's exact tests were used for statistical analysis . RESULTS Of 1584 women enrolled in the study , 162 were positive for sickle cell trait . Sickle cell trait-positive women were older than the sickle cell trait-negative women ( 24.4 + /- 4.6 vs 23.0 + /- 4.4 years , p < 0.001 ) , but there was no significant difference in parity . The rate of preeclampsia was significantly increased in sickle cell-positive women ( 24.7 % vs 10.3 % , p < 0.0001 ) . There was no significant difference in the rate of chronic hypertension , diabetes , or smoking .  Parous sickle cell-positive women more frequently gave a history of preeclampsia in a previous pregnancy ( 21.4 % vs 9.3 % , p < 0.0001 ) . There was a statistically significant decrease in gestational age at delivery and birth weight in sickle cell trait-positive women ( 36.7 + /- 2.7 vs 37.7 + /- 3.0 weeks , p < 0.0001 ; and 3082 + /- 591 vs 3369 + /- 573 gm , p < 0.0001 ) . The rate of postpartum endometritis was significantly increased in the women positive for sickle cell trait ( 12.3 % vs 5.1 % , p < 0.001 ) , although both groups had a similar cesarean section rate ( 14.8 % vs 12.6 % , not significant ) . CONCLUSION This is the first prospect i ve study to demonstrate that sickle cell trait-positive women are at significantly higher risk for development of perinatal complications that have traditionally been associated with sickle disease Forty-three homozygous ( SS ) female sickle cell anemic patients with a history of at least one painful crisis per month and desiring a reversible contraceptive were administered DMPA/3 months or Microgynon monthly . A third group of 16 surgically sterilized patients served as control . Patients were followed for 1 year to assess possible effects of the contraceptives on the patients ' painful crises . No changes were observed in any of the groups in the hematological parameters . At the end of the study , 70 % of the patients receiving DMPA were pain-free and only 16 % of those still reporting painful crises rated them as intense . Patients receiving Microgynon also had an amelioration of the painful crises , although at a lower rate ; after 12 months , 45.5 % still experienced some crises . Although less marked than in the other groups , 50.5 % of the control patients also reported an improvement of their painful crisis , which may be a result of closer medical care Objective To determine the maternal and fetal outcomes of pregnancy in women with sickle cell disease . Methods The subjects were part of a cohort recruited from 19 centers for a prospect i ve study of the clinical course of sickle cell disease . Each participant was evaluated using a structured protocol in which steady-state data and information on both sickle- and non-sickle-related events were colleted . The rates of antepartum and intrapartum complications were tallied for pregnancies carried to delivery . Fetal outcome was assessed according to gestational age , birth weight , and Apgar score . Differences among genotypes in event rates were assessed using Fisher exact test . Differences in gestational age and birth weight , and predictors of these outcomes , were assessed using analyses of covariance . Results Two hundred eighty-six of the 445 reported pregnacies proceeded to delivery . Non-sickle-related antepartum and intrapartum complication rates were comparable with those of African-American women who did not have sickle cell disease . One of the two deaths observed during this study was directly related to the presence of sickle cell disease . Rates of maternal morbidity from sickle cell disease were the same during pregancy as during the nonpregnant state . Ninety-nine percent of those pregnancies carried to delivery result ed in a live birth . Twenty-one percent of the infants born to women of the SS genotype were small for gestational age ( SGA ) . Preclampsia and acute anemic events were identified as risk factors for SGA infants . Conclusion Those caring for women with sickle cell disease should support them if they desire to have children 16 male and 28 female patients experiencing moderately severe pain during episodes of sickle-cell disease at least once in 3 months with little or no fever or exacerbations of jaundice were selected for a cross-over trial of low doses of steriods against saline solution . The patients each completed 4 - 6 months of treatment . All patients were on regular folates and had high or normal serum-iron values . Weights ranged from 24 - 134 pounds and ages from 2 - 35 years . Male patients were r and omly assigned to either testosterone in oil ( 10 mg in 1 ml ) or physiological sodium chloride solution ( 1 ml ) . Females were r and omly assigned to progesterone in oil ( 10 mg in 1 ml ) or physiological saline solution . A score was computed each month reflecting the severity , duration , and frequency of episodes of pain . About 80 % of the individuals on steriods had good responses and about the same proportion of the sodium chloride group had very poor responses . 22 of the original 31 patients stopped taking saline injections after the 1st 2 weeks . The packed-cell volumes in the steroid group rose during the period of steroid injections , while there was no appreciable change in the sodium chloride group . There were no sex differences in the pattern of response and no deleterious side effects were noted OBJECTIVE To assess the safety of Norplant contraceptive implant use by women with mild-moderate homozygous sickle cell disease ( HbSS ) . METHOD Prospect i ve observation of women pre- and post-insertion of Norplant  , with each woman serving as her own control . PARTICIPANTS 25 women 18 - 40 years of age who attended a hospital sickle cell clinic ; post-insertion data were available for 23 women . OUTCOME MEASURES Changes in hematologic parameters including PCV , MCV , reticulocytes , ISCs , HbF and bilirubin ; changes in biochemical parameters including HDL cholesterol , aspartate transaminase , alkaline phosphate , serum creatinine and serum albumin . RESULT With a mean follow-up of 12.4 months ( range 1 - 29 months ) , there were no clinical ly or statistically significant group or individual changes in the hematologic or biochemical parameters after Norplant insertion . CONCLUSION Norplant appears to be a safe and appropriate contraceptive for women with mild-moderate HbSS disease 
    Output:
    
CONCLUSION While data are limited , there is no evidence to suggest that hormonal contraceptive use among women with sickle cell disease is associated with an increased risk of clinical complications