To assess the efficacy and safety of prostaglandin in inducing labor in pregnant women with one previous cesarean section. Secondly, to evaluate predictors of successful vaginal delivery in cervical ripening by prostaglandin in these women.

This was an observational, retrospective, single-center study conducted in a type 3 maternity unit at Bicêtre University Hospital between January 1, 2013 and December 31, 2016. Patients with one previous cesarean section, a singleton pregnancy, a fetus in the cephalic presentation with a medical indication for induction of labor and an unfavorable cervix (Bishop score less than 6) were included in the study. Cervical ripening was performed using a dinoprostone intravaginal device for a duration of 24 h.

A total of 153 patients were included in the study. The rate of vaginal delivery was 55.6 % (85/153) overall and 78.3 % (36/46) in the subgroup of 46 women with a previous vaginal delivery before or after the cesarean section.

There was no difference in neonatal and maternal morbidity (defined by intraoperative wounds or postpartum hemorrhage or uterine rupture) and mortality between women who delivered vaginally and women who had a cesarean section. The two cases of complete uterine rupture have been reported for patients whose labor was induced by intravaginal prostaglandin followed by intravenous oxytocin. The total maternal morbidity rate was 11.8 % (n = 8/68) in the case of emergency cesarean section.

Predictors of vaginal delivery were a history of vaginal delivery, the onset of labor following cervical ripening, and a higher Bishop score before and after the 24 h following the cervical ripening.

Cervical ripening by prostaglandin after previous cesarean delivery has a 56 % success rate, with a 1.3 % risk of uterine rupture, especially when prostaglandin is combined with oxytocin. Low-risk patients should be identified to propose cervical ripening by prostaglandin.