Economic analysis of use of pessary to prevent preterm birth in women with multiple pregnancy (ProTWIN trial)

Objective To assess the cost-effectiveness of a cervical pessary to prevent preterm delivery in women with a multiple pregnancy. Methods The study design comprised an economic analysis of data from a randomized clinical trial evaluating cervical pessaries (ProTWIN). Women with a multiple pregnancy were included and an economic evaluation was performed from a societal perspective. Costs were estimated between the time of randomization and 6 weeks postpartum. The prespecified subgroup of women with a cervical length (CL) < 25 ^th centile (< 38 mm) was analyzed separately. The primary endpoint was poor perinatal outcome occurring up to 6 weeks postpartum. Direct medical costs and health outcomes were estimated and incremental cost-effectiveness ratios for costs to prevent one poor outcome were calculated. Results Mean costs in the pessary group (n = 401) were €21 783 vs €21 877 in the group in which no pessary was used (n = 407) (difference, -€94; 95% CI, -€5975 to €5609). In the prespecified subgroup of women with a CL < 38 mm we demonstrated a significant reduction in poor perinatal outcome (12% vs 29%; RR, 0.40; 95% CI, 0.19-0.83). Mean costs in the pessary group (n = 78) were €25 141 vs €30 577 in the no-pessary group (n = 55) (difference, -€5436 (95% CI, -€11 001 to €1456). In women with a CL < 38 mm, pessary treatment was the dominant strategy (more effective and less costly) with a probability of 94%. Conclusion Cervical pessaries in women with a multiple pregnancy involve costs comparable to those in women without pessary treatment. However, in women with a CL < 38 mm, treatment with a cervical pessary appears to be highly cost-effective.