Effects of Acceptance and Commitment Therapy on Emotional Regulation in Women with Postpartum Depression: A Quasi-Experimental Controlled Study

Objective: This study evaluated the effectiveness of Acceptance and Commitment Therapy (ACT) in improving emotional regulation among women with postpartum depression.

Methods and Materials: This applied quasi-experimental study used a pretest–posttest control-group design. The population included women with postpartum depression referred to psychological clinics in Tehran in 2023. From 80 eligible women, 40 participants aged 25–40 years who met the inclusion criteria were selected by purposive sampling and randomly assigned to an ACT group (n = 20) or a control group (n = 20). The intervention group received eight 2-hour group ACT sessions based on Hayes’ protocol, while the control group received no intervention. Data were collected using the Beck Depression Inventory and the Emotion Regulation Questionnaire by Gross and John. Descriptive statistics, Kolmogorov–Smirnov tests, ANCOVA, and MANCOVA were performed using SPSS-23.

Findings: The mean total emotional regulation score increased from 36.85 ± 5.36 to 41.75 ± 5.32 in the ACT group, compared with 37.20 ± 5.65 to 37.55 ± 5.56 in the control group. ANCOVA showed a significant intervention effect on emotional regulation (F = 4.852, p = 0.034, η² = 0.119). MANCOVA was significant for the emotional regulation components (Pillai’s Trace = 0.670, F = 37.596, p < 0.001). ACT significantly improved cognitive reappraisal (F = 4.856, p = 0.034, η² = 0.113) and expressive suppression (F = 58.299, p < 0.001, η² = 0.605).

Conclusion: ACT significantly improved emotional regulation in women with postpartum depression. Incorporating ACT-based strategies, particularly acceptance, mindfulness, values clarification, and committed action, may help enhance adaptive emotional functioning in postpartum women.