A comparative trial of labor induction with misoprostol versus oxytocin

To determine the efficacy and safety of intravaginal misoprostol compared with intravenous oxytocin in cervical ripening and labor induction.

The study was carried out at the Department of Obstetrics and Gynecology at the Hospital Loayza, Lima, Peru. The sample included 123 pregnant women with any indication for labor induction. The study was prospective and randomized. We compared the effect of 50 micrograms of intravaginal misoprostol administered every 4 h up to 600 micrograms with that observed using the standard protocol of oxytocin by continuous infusion.

57 patients with misoprostol (group 1) and 63 with oxytocin (group 2) were enrolled. Delivery occurred in 45 patients (78.9%) in group 1 and in 37 (58.7%) in group 2 (P < 0.017). Complications including tachysystole, uterine hypertony and hyperstimulation were higher in group 1, 21.1% than in group 2, 7.9% (P < 0.04). The incidence of cesarean section in both groups was similar to the overall incidence in our center. No differences were observed between groups in perinatal and postpartum adverse outcomes. The interval from start of induction to vaginal delivery was significantly shorter in the oxytocin group (8.4 +/- 4.1 vs. 11.3 +/- 6.9 h, P < 0.005).

Intravaginal administration of misoprostol is a safe and effective alternative for cervical ripening and labor induction. Maternal and neonatal complications did not increase significantly.