Misoprostol combined with cervical single or double balloon catheters versus misoprostol alone for labor induction of singleton pregnancies: a meta-analysis of randomized trials

Objective: To compare the effect of misoprostol combined with a cervical single or double-balloon catheter versus misoprostol alone for labor induction of singleton pregnancies with an unfavorable cervix. Methods: Systematic review and meta-analysis of randomized controlled trials (RCTs) regarding the comparison of two schemes for labor induction of singleton cephalic pregnancies with a Bishop score ≤7 and no contraindication for vaginal delivery. Six research databases were searched for articles published in all languages up to 10 May 2018 comparing misoprostol (oral or vaginal) in combination with a cervical placed single or double balloon catheter versus misoprostol treatment alone. Random effects models and inverse variance were used for meta-analyses. Summary measures were mean differences (MDs) and risk ratios (RRs) with 95% confidence interval (CI). Risk of bias was evaluated with the Cochrane tool and publication bias was assessed with Begg’s and Egger’s tests. Results: Fifteen RCTs reported predefined outcomes. Pooled analyses showed that the combined treatment (misoprostol + catheter) was associated with a shorter induction to delivery time interval (MD = −1.99 hours; 95% CI: −3.42, −0.56); in addition to fewer uterine hyperstimulations (RR = 0.39; 95% CI: 0.23, 0.67) and Neonatal Intensive Care Unit (NICU) admissions (RR = 0.75; 95% CI: 0.58, 0.97) as compared to misoprostol alone. There were no significant differences in RRs for tachysystole, chorioamnionitis, cesarean delivery rate, birthweight, and Apgar score at 5 minutes. Conclusion: The combined use of misoprostol and a cervical balloon catheter reduces the intervention to delivery time interval and number of NICU admissions in women induced with an unfavorable cervix.