A comparison between 50 mcg oral misoprostol every 4 hours and 6 hours for labor induction: a prospective randomized controlled trial.

OBJECTIVE: To compare the effectiveness and safety between 50 mcg oral misoprostol every 4 hours and 6 hours for labor induction. DESIGN: A prospective randomized controlled trial. SETTING: Department of Obstetrics & Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand. SUBJECTS: Eighty nine pregnant women of at least 34 weeks' gestation with indications for labor induction in the condition of unfavourable cervix (Bishop score < or = 4) and no contraindication to prostaglandin therapy. INTERVENTIONS: All pregnant women were randomized to receive either 50 mcg misoprostol orally every 4 hours or 6 hours. MAIN OUTCOME MEASURES: Treatment interval from induction to vaginal delivery, maternal and neonatal complication. RESULTS: The mean treatment intervals from induction to vaginal delivery were 22.10 +/- 18.49 hours and 20.91 +/- 11.98 hours in the misoprostol group every 4 hours and 6 hours, respectively. The treatment intervals between the two groups were not statistically significant. There was also no significant difference between both groups with regard to maternal and neonatal complications. CONCLUSION: The effectiveness in terms of treatment interval from induction to vaginal delivery were comparable between the two groups, but administration of misoprostol every 6 hours was found to have a slightly shorter interval, although it did not reach statistical significance. No serious maternal and neonatal complication was demonstrated in both groups. Either regimen in this study can be an alternative for labor induction.