Comparative Evaluation of 50 Microgram Oral Misoprostol and 25 Microgram Intravaginal Misoprostol for Induction of Labour at Term: A Randomized Trial

Abstract

ObjectivesTo assess and compare the efficacy and safety of 50 μg oral misoprostol and 25 μg intravaginal misoprostol for induction of labour at term. MethodsThis non-blinded, randomized clinical trial included 228 pregnant women at term with obstetric or medical indications for induction of labour. Women either took 50 μg misoprostol orally (two 25 μg tablets) or had one 25 μg tablet of misoprostol inserted in the posterior vaginal fornix. In each group, misoprostol administration was repeated every four hours in the same dose until regular uterine contractions were established or to a maximum of five doses. Time to delivery and outcome data for each group were compared. ResultsOf the 228 women, eight (3.5%) were excluded from the analysis as they withdrew their consent after randomization. Mean induction-to-delivery interval was similar in both groups (21.22 hours in the oral group vs. 20.15 hours in the vaginal group; P = 0.58). There was no significant difference between the groups with respect to the number of women who delivered within 24 hours or who required oxytocin augmentation of labour, the mode of delivery, and neonatal outcomes (P > 0.05). Uterine hyperstimulation occurred in two women who received misoprostol vaginally, but not in any of the women in the oral misoprostol group. ConclusionOral misoprostol in a dose of 50 μg every four hours, to a maximum of five doses, has the potential to induce labour as safely and effectively as 25 μg misoprostol administered vaginally every four hours.