Cost effectiveness of outpatient balloon catheter induction of labor compared with inpatient prostaglandin: Economic analysis alongside the OBLIGE randomised controlled trial

Background Induction of labor is a common obstetric intervention. Numerous methods and protocols for achieving cervical ripening exist, including outpatient management using a balloon catheter. Objective (s) This study aims to perform a cost-effectiveness analysis of the OBLIGE trial, a multicentre randomised controlled trial comparing outpatient single balloon catheter for cervical ripening to inpatient vaginal prostaglandin (PG), using cesarean births avoided as the primary outcome measure. Study Design Using a health service payer perspective, this cost-effectiveness analysis considers the direct healthcare costs (2021 NZ Dollars) from randomisation to 42 days post-birth. Clinical outcomes were identified from trial data collection, while healthcare resource use and costs were identified from routinely collected national data. Results Across bootstraped replicates, the difference in mean costs -$256 (95% CI $-1172 to $639) and caesarean births avoided -5.67% (95% CI -11.09 to 0.07) did not reach statistical significance. These results suggest that balloon catheters may be considered cost-effective where decision makers value a cesarean birth avoided below $4,519. Subgroup analysis demonstrates outpatient balloon catheters are dominated (less effective and more costly) among parous women. Conclusion (s) Immediate costs are unlikely to be critical in decisions about the use of outpatient balloon catheter induction of labor. In future economic analyses, consideration of longer-term costs and clinical outcomes resulting from cesarean birth, and any quality of life impacts of outpatient induction, would be important to clarify the cost-effectiveness of this intervention.