Dinoprostone Versus Balloon Catheter for Cervical Ripening in Multiparous Women Undergoing Induction of Labor: A Retrospective Cohort Study

AIM: To compare maternal and neonatal outcomes of induction strategies initiated with slow-release vaginal dinoprostone (10 mg) or balloon catheter in multiparous women undergoing term induction of labor with an unfavorable cervix. METHODS: This retrospective cohort study included 802 multiparous women with singleton pregnancies at ≥ 37 weeks' gestation, Bishop score < 8, and a medical indication for induction of labor at a tertiary university-affiliated center (2020-2025). Women underwent cervical ripening with either a balloon catheter (n = 522) or a slow-release vaginal dinoprostone insert (n = 280). The co-primary outcomes were the cervical ripening-to-delivery interval and delivery within 24 h. Multivariable analyses identified independent predictors of delivery interval and cesarean birth. RESULTS: Compared with balloon catheter, dinoprostone was associated with a shorter cervical ripening-to-delivery interval (11.6 vs. 19.4 h; p < 0.001). Delivery within 12 h was more frequent with dinoprostone (51.4% vs. 26.1%; p < 0.001), whereas delivery within 24 h did not differ significantly between groups (75.7% vs. 71.1%; p = 0.183). Dinoprostone was also associated with a higher spontaneous vaginal delivery rate (95.0% vs. 90.0%; p = 0.015) and a lower cesarean delivery rate (3.2% vs. 8.2%; p = 0.006). Intrapartum fever occurred less frequently with dinoprostone (1.4% vs. 4.2%; p = 0.036), while no statistically significant differences were observed in measured neonatal outcomes, including NICU admission. CONCLUSIONS: Among multiparous women undergoing term induction of labor, dinoprostone was associated with a shorter cervical ripening-to-delivery interval, higher spontaneous vaginal delivery rates, and lower cesarean rates than balloon catheter. Delivery within 24 h was similar between groups, with no significant differences in measured neonatal outcomes.