Outpatient cervical ripening with balloon catheters: A Bayesian network meta-analysis of randomized controlled trials

Background: One in four labors are induced. The process of cervical ripening can be lengthy and pre-labor hospitalization is required. Outpatient cervical ripening can be an attractive alternative.

Objectives: To evaluate the efficacy and safety of outpatient cervical ripening with a balloon catheter compared with inpatient balloon catheter or prostaglandin E₂ (PGE₂).

Search strategy: The PubMed, MEDLINE, Embase, ClinicalTrials.gov, and Cochrane Library databases were searched from their inception to October 15, 2022.

Selection criteria: Randomized controlled trials comparing the outpatient balloon catheter with inpatient balloon catheter or inpatient PGE₂ for term cervical ripening.

Data collection and analysis: Bayesian network meta-analysis was performed. The primary outcome was the cesarean delivery rate. The secondary outcomes included instrumental delivery, the time from intervention-to-birth, oxytocin augmentation, total hospital duration, and maternal/neonatal adverse events.

Main results: Twenty-nine randomized controlled trials with a total of 6004 participants were identified. No difference in the cesarean delivery rate was revealed among the three interventions. Compared with inpatient balloon catheter, outpatient balloon catheter had shorter total hospital duration (mean difference -8.58, 95% confidence interval -17.02 to -1.10). No differences were revealed in the time from intervention-to-birth, instrumental delivery, postpartum hemorrhage, 5-min Apgar score less than 7, umbilical cord arterial pH less than 7.1, and neonatal intensive care unit admission among the three interventions.

Conclusions: Outpatient balloon catheter in low-risk term pregnancies is an available option that could be considered for cervical ripening. The safety and effectiveness are comparable to inpatient cervical ripening methods.