Objective: To examine the differences in perinatal outcomes among women with a prior preterm birth who received cerclage compared with cerclage plus 17α-hydroxyprogesterone caproate.
Methods: Women with transvaginal cerclage placement and a prior delivery between 16 and 36 weeks of gestation were identified over a 10-year period (July 2002 to May 2012) in this retrospective cohort study. Exclusion criteria were delivery at another institution, abdominal cerclage, multiple gestations, and major fetal anomalies. Maternal demographics, gestational age at cerclage, gestational age at delivery, preterm prelabor rupture of membranes (PROM), and birth weight were compared between women with a cerclage and cerclage plus 17α-hydroxyprogesterone caproate. The primary outcome was delivery at less than 24 weeks of gestation.
Results: Of the 411 women who had a cerclage, 260 met inclusion criteria. Of these, 171 received a cerclage alone and 89 received cerclage plus 17α-hydroxyprogesterone caproate. The two groups were not different with respect to maternal demographics and gestational age at cerclage. There was a significant difference among those who received indomethacin at the time of cerclage, betamethasone administration, and history of a loop electrosurgical excision procedure-cold knife cone and cerclage. Delivery at less than 24 weeks of gestation occurred in 6% of women receiving both 17α-hydroxyprogesterone caproate and cerclage compared with 16% in the cerclage only group (odds ratio [OR] 0.31, 95% confidence interval 0.10-0.78, P=.01). In the multivariate analysis controlling for indomethacin use, prior cerclage, and loop electrosurgical excision procedure-cold knife cone there was a 73% reduction in delivery in the combined treatment group compared with cerclage alone (adjusted OR 0.26, P=.02). A multivariant analysis was conducted with correction for indomethacin at the time of cerclage, prior cerclage, and loop electrosurgical excision procedure-cold knife cone and cerclage surgery. Even after controlling for significant variables, there remained a 73% reduction in delivery at less than 24 weeks of gestation in the cerclage plus 17α-hydroxyprogesterone caproate cohort (adjusted OR 0.26, P=.02).
Conclusion: Women receiving transvaginal cerclage plus 17α-hydroxyprogesterone caproate had a 69% relative reduction in delivery at less than 24 weeks of gestation when compared with women receiving cerclage alone. We found no difference in overall preterm delivery or preterm PROM. In this cohort, compared with cerclage alone, the likelihood of a viable neonate improves with both treatments.