The efficacy and safety of oral and vaginal misoprostol versus dinoprostone on women experiencing labor: A systematic review and updated meta-analysis of 53 randomized controlled trials

Background: Induction of labor is the process of artificially stimulating the uterus to start labor before the spontaneous onset of labor. It has several medical indications. Commonly used agents are vaginal misoprostol, vaginal prostaglandin E2 (dinoprostone), and oral misoprostol. Methods: Through October 2023, a literature review was carried out in Cochrane, PubMed, Web of Science, and Scopus to identify randomized clinical studies assessing if oral and vaginal misoprostol has better efficacy of induction of labor over vaginal prostaglandin E2 or dinoprostone as a primary outcome. The data were pooled as mean difference, risk ratio, and 95% confidence interval. Results: Fifty-three RCTs involving 10,455 patients showed a statistically significant difference in the overall success rate of induction between the misoprostol and prostaglandins E2 (PGE2) groups. They required less additional oxytocin compared to the PGE2 groups. The frequency of tachysystole, uterine hyperstimulation, abnormal cardiotocography, meconium-stained amniotic fluid, and Apgar score <7 at 1 minute were all higher in misoprostol groups than in PGE2 groups. No difference was found in cesarean section, fever, Neonatal Intensive Care Unit admission, or Apgar scores at 1 minute or 5 minutes. Conclusion: Vaginal misoprostol is more effective at inducing labor but may be less safe than vaginal dinoprostone. Oral misoprostol is generally as safe as vaginal dinoprostone. Vaginal dinoprostone requires lower doses but may need more oxytocin administration.