Oral Versus Vaginal Misoprostol for Labor Induction: A Prospective Comparative Study of Maternal and Neonatal Outcomes

Abstract

Background: Labour induction is increasingly common, and misoprostol is widely used due to its efficacy, affordability, and stability. The optimal administration route remains debated, particularly regarding efficacy and safety.

Objective: To compare the efficacy and safety of low-dose oral versus vaginal misoprostol for labor induction and evaluate associated maternal and neonatal outcomes.

Methods: Pregnant women requiring labor induction were prospectively allocated to receive either oral misoprostol (25 µg every 2 hours) or vaginal misoprostol (25 µg every 4 hours), up to eight doses. The primary outcomes were mode of delivery and number of doses required for vaginal delivery. The secondary outcomes included maternal and neonatal outcomes.

Results: Vaginal misoprostol increased vaginal delivery rates (94% vs. 81%, P<0.05) and reduced cesarean sections (6% vs. 19%) compared with oral administration. Fewer doses were required (2.81 ± 0.91 vs. 4.46 ± 1.45, P<0.0001). Maternal adverse events were lower (6% vs. 19%, P=0.010), with uterine hyperstimulation and rupture observed only in the oral group. Neonatal outcomes favored vaginal administration, with higher Apgar scores and fewer neonatal intensive care unit admissions (26.2% vs. 45.2%, P<0.05), while meconium-stained liquor was similar between groups.

Conclusion: Low-dose vaginal misoprostol was associated with improved labor induction outcomes compared with oral administration, including a higher rate of vaginal delivery, fewer required doses, improved maternal and neonatal outcomes. However, given the non-randomized design and baseline imbalances between the groups, these findings should be interpreted with caution and confirmed by randomized controlled trials.