Safety and Efficacy of Dinoprostone and Misoprostol Vaginal Inserts for Labor Induction [11H]

INTRODUCTION: The purpose of this study was to compare the safety and efficacy of the removable dinoprostone vaginal inserts (DVI) and misoprostol vaginal inserts (MVI) using a pooled analysis. METHODS: Data were obtained from a pooled analysis of three phase II/III trials that randomized 1,925 women with longer than 36 0/7 weeks gestation with a modified Bishop score of 4 or less to DVI (mean release rate 0.3 mg/h) (n=1,116) or MVI (mean release rate 7 µg/h) (n=809). The distribution of time to vaginal delivery in both treatment groups was assessed using a log-rank test. Fisher exact test was used to test whether treatment was associated with peripartum adverse events. Data are presented as mean±standard deviation. RESULTS: Certain adverse events were significantly less common with DVI compared to MVI, including meconium in amniotic fluid (12.2% vs 17.6%; P=.001), abnormal labor affecting fetus (ie, hyperstimulation syndrome) (4.2% vs 10.6%; P < .001), and fetal acidosis (0.04% vs 1.2%; P=.030), while chorioamnionitis was more common with DVI compared to MVI (7.3% vs 4.9%, P=.037). There were no significant differences between treatment groups for fetal heart rate disorder, postpartum hemorrhage, and arrested labor; neonatal intensive care unit admissions and cesarean delivery incidence were similar between groups. Time to vaginal delivery (hours) was longer with DVI compared to MVI (25.2±12.8 vs 19.0±10.7, P < .001). CONCLUSION: DVI use was associated with decreased rates of meconium, abnormal labor affecting fetus, and fetal acidosis as well as with higher rates of chorioamnionitis and a slower time to delivery compared to MVI.