Comparison of vaginal misoprostol tablets and prostaglandin E2 gel for the induction of labor in premature rupture of membranes at term: a randomized comparative trial.

Aim:  To compare immediate induction with vaginal misoprostol tablets and immediate induction with vaginal dinoprostone (naturally occurring prostaglandin E2 [PGE2]) gel in women with premature rupture of membranes (PROM) at term.

Methods: Two hundred and twelve women with PROM at term were assigned randomly to receive either an intravaginal 25 µg misoprostol tablet, 4-hourly, with a maximum of five doses, or 0.5 mg intravaginal PGE2 gel, 6-hourly, with a maximum of two doses. The primary outcome measures were the admission-to-delivery interval and the induction-to-delivery interval. Secondary outcomes included cesarean section rate, mode of delivery, and maternal and neonatal safety outcome. Results were calculated applying Fisher's exact test, χ2-test, t-test and calculating the P-value using an alpha level of 0.05 for Type I errors.

Results: The mean time from admission to delivery was 13.53 h in the misoprostol group and 12.30 h in the PGE2 group (P = 0.090). The induction-to-delivery interval was also comparable between the groups (10.75 h vs. 9.37 h), while the cesarean section rate did not differ significantly between them (7.61% vs. 15.30%). More women in the misoprostol group had an instrumental delivery (12.38% vs. 2.94%). The only significant difference in neonatal outcome was a greater number of babies born with Apgar score < 7 at 1 min in the misoprostol group. Maternal outcomes were not significantly different, except for a higher number of digital vaginal examinations in the misoprostol group.

Conclusion: Vaginal misoprostol is equally efficacious in labor induction and demonstrates a similar fetal and maternal safety profile to PGE2 gel.