Outpatient Oral Misoprostol for Prolonged Pregnancies: A Pilot Investigation

ABSTRACT

We evaluated the effectiveness of oral misoprostol for outpatient cervical ripening and labor induction in prolonged pregnancies. We performed a randomized, double-blind, placebo-controlled study of women at 40 to 42 weeks' gestation with well-dated pregnancies, singleton gestations, Bishop scores less than 6, vertex presentations, and intact membranes. Subjects received either oral misoprostol 100 μg or placebo daily for 3 days unless the subject developed significant cervical change or began labor spontaneously. Study drug was repeated every 24 hours for a maximum of three doses if subjects did not develop significant cervical change or enter labor. Induction of labor was not allowed while the subject was enrolled in the study. Forty-three subjects were randomized to receive misoprostol and 44 randomized to receive placebo. A significant difference was noted in reduction of time from study entry to both active phase (p < 0.001) and delivery (p < 0.001) in the misoprostol group. Fewer women remained undelivered after the 72-hour study period in the misoprostol group. There were no differences in route of delivery or neonatal outcomes between groups. Conclusion: Daily administration of oral misoprostol over 3 days to women with prolonged pregnancies shortened time intervals from dosing to entry into active labor and delivery compared with placebo.

KEYWORDS

Misoprostol - cervical ripening - prolonged pregnancy

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