Associations of hypertensive disorders of pregnancy and outcomes of labor induction with prostaglandin vaginal inserts

Abstract

ABSTRACTObjective: To evaluate the association between hypertensive (HTNsive) disorders of pregnancy and outcomes of labor induction, in two cohorts of women induced with either misoprostol vaginal insert (MVI) or dinoprostone vaginal insert (DVI). Study Design: This investigation was a post-hoc analysis of data from three Phase II and III, multi-center, double blind, randomized controlled trials of women induced with identical efficacy endpoints. A competing risk framework investigated the association between HTNsive disorders of pregnancy and the time-to-event endpoints of onset of active labor and vaginal delivery. We analyzed the overall incidence of the competing risk, cesarean delivery, by logistic regression to identify potential differences between the proportion of patients with cesarean and vaginal deliveries for each cohort. Results: 401 women with HTNsive disorders during pregnancy underwent induction of labor in these studies (175 with DVI and 226 with MVI). Significant differences were noted in the cumulative incidence of vaginal delivery 24 hours following insertion between the non-HTNsive and HTNsive groups for both treatments, (57.1% vs. 47.4% (p=0.023) among MVI patients and 39.9% vs. 27.2% (p=0.017) among DVI patients). However, upon adjusting for potential confounders, the estimated relative rates of vaginal delivery among HTNsive vs. non-HTNsive patients was 0.947 (95% CI (0.637, 1.371), p=0.631) and 0.904 (95% CI (0.735, 1.113) p=0.341) within the MVI and DVI sub-groups respectively. Conclusion: After adjustment for confounders, such as BMI, baseline modified Bishop score and gestational age, time-to-event outcomes for induction of labor using MVI or DVI in HTNsive women are not significantly different from non-HTNsive women