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.