Induction of Labor at Term with Oral Misoprostol or as a Vaginal Insert and Dinoprostone Vaginal Insert – A Multicenter Prospective Cohort Study

Introduction The efficacy, safety, and perinatal outcome of oral misoprostol (OM), a misoprostol vaginal insert (MVI), and a dinoprostone vaginal insert (DVI) for induction of labor at term was examined in a prospective multicenter cohort study (ethics committee vote 4154–07/14). The primary aims of the study were the induction-birth interval (IBI), the cumulative delivery rates after 12 h, 24 h, and 48 h as well as the mode of delivery. Method 322 pregnant women were included in four German tertiary perinatal centers (MVI 110, DVI 64, OM 148). They did not vary in age or BMI. Statistical analysis was carried out using a multivariate linear regression analysis and binary logistic regression analysis. Results With regards to the median IBI, MVI and OM were equally effective and superior to the DVI (MVI 823 min [202, 5587]; DVI 1226 min [209, 4909]; OM 847 min [105, 5201]; p = 0.006). Within 24 hours, 64% were able to deliver with DVI, 85.5% with MVI and 87.5% with OM (p < 0.01). The rates of secondary Caesarean sections (MVI 24.5%; DVI 26.6%; OM 18.9%) did not differ significantly. Uterine tachysystole was found in 20% with MVI, 4.7% with DVI and 1.4% with OM (p < 0.001). A uterine rupture did not occur in any of the cases. Perinatal acidosis occurred (umbilical cord arterial pH < 7.10) in 8.3% with MVI, 4.7 with DVI and 1% with OM (p = 0.32). Neonatal condition was only impaired in three cases (5-minute Apgar score < 5). Summary Induction of labor at term using the prostaglandins misoprostol and dinoprostone is an effective intervention that is safe for the mother and child. Oral application of misoprostol demonstrated the highest efficacy while maintaining a favorable safety profile.