Randomized comparison of oral misoprostol and oxytocin for labor induction in term prelabor membrane rupture

Abstract

Objectives: To compare labor induction intervals between oral misoprostol and intravenous oxytocin in women who present at term with premature rupture of membranes.

Methods: One hundred eight women were randomly assigned to misoprostol 50 microg orally every 4 hours as needed or intravenous oxytocin. The primary outcome measure was time from induction to vaginal delivery. Sample size was calculated using a two-tailed alpha of 0.05 and power of 80%.

Results: Baseline demographic data, including maternal age, gestation, parity, Bishop score, birth weight, and group B streptococcal status, were similar. The mean time +/-standard deviation to vaginal birth with oral misoprostol was 720+/-382 minutes compared with 501+/-389 minutes with oxytocin (P = .007). The durations of the first, second, and third stages of labor were similar. There were no differences in maternal secondary outcomes, including cesarean birth (eight and seven, respectively), infection, maternal satisfaction with labor, epidural use, perineal trauma, manual placental removal, or gastrointestinal side effects. Neonatal outcomes including cord pH, Apgar scores, infection, and admission to neonatal intensive care unit were not different.

Conclusion: Although labor induction with oral misoprostol was effective, oxytocin resulted in a shorter induction-to-delivery interval. Active labor intervals and other maternal and neonatal outcomes were similar.