OBJECTIVES: The OptiBIRTH study incorporates a multicentre cluster randomised trial in 15 sites across three European countries. The trial was designed to test a complex intervention aimed at improving vaginal birth after caesarean section (VBAC) rates through increasing women’s involvement in their care. In preparation for conducting the health economic analysis part of the OptiBIRTH study, an analysis of a hypothetical cohort was performed to estimate the costs and health effects of VBAC compared to elective repeat caesarean delivery (ERCD) for low-risk women in four European countries. METHODS: A decision-analytic model was developed to estimate the costs and the health effects, measured using Quality Adjusted Life Years (QALYs), of VBAC compared with ERCD. A cost-utility analysis for the period from confirmation of pregnancy to 6 weeks postpartum was performed for a hypothetical cohort of 100,000 pregnant women in each of four different countries; Belgium, Germany, Ireland and Italy adopted a societal perspective. Where possible, transition probabilities, costs and health effects were adapted from data obtained from the respective countries, and country-specific thresholds were used to determine the cost-effectiveness of VBAC compared to ERCD. Deterministic and probabilistic sensitivity analyses were conducted to examine the uncertainty of model assumptions. RESULTS: VBAC was a dominant strategy compared to ERCD and resulted in a reduction in costs, ranging from €4,639,037 (Germany) to €71,768,175 (Ireland), and gains in QALYs ranging from 5,858 (Italy) to 7,573 (Germany) per 100,000 women birthing in each country. The ICER results differed from -€569/QALY (Germany), -€2,113/QALY (Belgium), -€3,247/QALY (Italy) to -€11,021/QALY (Ireland). CONCLUSIONS: In all four countries, VBAC was associated with costs savings and gains in QALYs compared to ERCD for low-risk women. This is important for health service managers, economists and policy makers concerned with maximising health benefits within limited and constrained resources.