Misoprostol for labor induction in women with term premature rupture of membranes: a meta-analysis

OBJECTIVE: To systematically review published data evaluating the comparative use of misoprostol with placebo/expectant management or oxytocin for labor induction in women with term (> or = 36 weeks of gestation) premature rupture of membranes. DATA SOURCES: PubMed (1966-2005), Ovid (1966-2005), CINAHL, The Cochrane Library, ACP Journal Club, OCLC, abstracts from scientific forums, and bibliographies of published articles were searched using the following keywords: premature rupture of membranes, misoprostol, labor induction, and cervical ripening. Primary authors were contacted directly if the data sought were unavailable or only published in abstract form. METHODS OF STUDY SELECTION: Only randomized controlled trials evaluating the efficacy and safety of misoprostol in comparison with placebo or expectant management (n = 6) and oxytocin (n = 9) published in either article or abstract form were analyzed and included in the meta-analysis. TABULATION, INTEGRATION, AND RESULTS: Studies were reviewed independently by all authors. Meta-analysis was performed, and the relative risks (RRs) were calculated and pooled for each study outcome. Misoprostol, compared with placebo, significantly increased vaginal delivery less than 12 hours (RR 2.71, 95% confidence interval [CI] 1.87-3.92, P < .001). Misoprostol was similar to oxytocin with respect to vaginal delivery less than 24 hours (RR 1.07, 95% CI 0.88-1.31, P = .50) and less than 12 hours (RR 0.98, 95% CI 0.71-1.35, P = .90). Misoprostol was not associated with an increased risk of tachysystole, hypertonus, or hyperstimulation syndrome when compared with oxytocin and had similar risks for adverse neonatal and maternal outcomes. CONCLUSION: Misoprostol is an effective and safe agent for induction of labor in women with term premature rupture of membranes. When compared with oxytocin, the risk of contraction abnormalities and the rate of maternal and neonatal complications were similar among the 2 groups.