Background: Uterine contractions and an appropriate cervix are two important factors in labor contributing to good pregnancy outcomes. Oxytocin and prostaglandins, such as misoprostol, are used for the induction of labor. Misoprostol is used for cervical ripening and labor induction. The aim of this trial was to compare the efficacy and safety of titrated oral misoprostol solution with oxytocin for labor induction in pregnant women with an unfavorable cervix.

Methods: In this randomized double-blind clinical trial, 140 women with a gestational age of 34-42 weeks and an unfavorable cervix were recruited. The participants had an indication for labor induction and had been referred to the Women's Hospital in Tehran, Iran between January 2010 and January 2011. The participants were randomly assigned to receive 20 µg/hour titrated oral misoprostol plus intravenous placebo or 6 mU/min oxytocin plus oral placebo. In case contractions were inadequate, the drug doses were gradually increased. Pharmacological complications, the mean interval from the start of induction till vaginal delivery and delivery type were monitored and analyzed in both groups.

Results: The mean interval from the start of induction till vaginal delivery in misoprostol group was shorter than the oxytocin group (11.07±3.42 vs. 14.87±3.21 hours, P=0.001). The frequency of pharmacological complications and vaginal or cesarean deliveries were similar between the two groups (P>0.05).

Conclusion: Use of titrated oral misoprostol is a safe and effective method for labor induction in pregnant women with unfavorable cervix. Misoprostol is associated with a shorter interval from induction to vaginal delivery than oxytocin.