Postpartum depression (PPD) poses significant challenges, affecting both mothers and children, with substantial societal and economic implications. Internet-based cognitive behavioral therapy interventions (iCBT) offer promise in addressing PPD, but their economic impact remains unexplored. This study aimed to evaluate the cost-utility of Be a Mom, a self-guided iCBT intervention, compared with a waiting-list control among postpartum women at high risk of PPD.

This economic evaluation was conducted alongside a 14-month randomized controlled trial adopting a societal perspective. Participants were randomized to Be a Mom (n = 542) or a waitlisted control group (n = 511). Self-report data on healthcare utilization, productivity losses, and quality-adjusted life years (QALYs) were collected at baseline, post-intervention, and 4 and 12 months post-intervention. Incremental cost-effectiveness ratios (ICERs) were calculated, and cost-effectiveness acceptability curves were generated using nonparametric bootstrapping. Sensitivity analyses were conducted to assess result robustness.

Over 14 months, Be a Mom generated a QALY gain of 0.0184 (0.0022, 0.0346), and cost savings of EUR 34.06 (−176.16, 108.04) compared to the control group. At a willingness to pay of EUR 20,000, Be a Mom had a 97.6 % probability of cost-effectiveness.

Results have limitations due to self-selected sample, potential recall bias in self-reporting, missing data, limited follow-up, and the use of a waiting-list control group.

This study addresses a critical gap by providing evidence on the cost-utility of an iCBT intervention tailored for PPD prevention. Further research is essential to identify scalable and cost-effective interventions for reducing the burden of PPD.