A systematic review of postpartum physical activity intervention mediators.

Objective: Regular physical activity (PA) is associated with many health benefits; however, up to 94% of postpartum individuals do not meet PA guidelines. Understanding mediators of postpartum PA behavior change interventions is essential to increase PA participation following childbirth. The purpose of this review was to identify putative mediators of postpartum PA interventions.

Method: Six databases were searched for primary or gray literature from inception until December 2023. Intervention studies of any language were included if they contained (a) individuals ≤ 12 months postpartum, (b) a PA intervention, (c) a no exercise or different exercise comparator, and (d) a change in PA and putative mediator outcome that could be classified with the theoretical domains framework (TDF). Results were categorized by mediation path, mediator TDF domain, and PA outcome.

Results: Twenty-eight articles (3,328 participants) were eligible, and summary effects for Paths AB, A, B, and C were calculated from two, 19, two, and 18 unique studies, respectively. For the mediation Path AB, we found very small effects from the domains of beliefs about capabilities (r = .08), beliefs about consequences (r = .02), environmental context and resources (r = .01), and social influences (r = .08). We found a small total effect (Path C, r = .12) of postpartum PA interventions on PA.

Conclusion: Future postpartum PA interventions should integrate components that increase outcomes under the domains of beliefs about capabilities, beliefs about consequences, environmental context and resources, and social influences. Further research that tests nonconscious mediators (e.g., PA habit, identity) is needed. (PsycInfo Database Record (c) 2025 APA, all rights reserved).