Effects of Peer-Led Walking With mHealth Technology on Exercise Behavior of Women With Overweight and Obesity From Pregnancy to Early Postpartum: A Randomized Controlled Trial

Background: Women with overweight or obesity tend to engage in low levels of exercise and face challenges in initiating and maintaining exercise throughout pregnancy. Aims: This study aimed to evaluate the effectiveness of a peer-led walking and mobile health (mHealth) app intervention on self-efficacy and change in exercise behavior stage, based on the transtheoretical model (TTM), of women with overweight or obesity from pregnancy to one month postpartum. Methods: The study was a randomized controlled trial with an experimental design. A total of 114 pregnant women (BMI ≥ 24 kg/m² and gestation < 16 weeks) were recruited from prenatal clinics in Taiwan from July 2021 to May 2022. The intervention group (IG) received the peer-led walking program with mHealth support, while the control group (CG) received standard antenatal care. Follow-ups were conducted at 24–28 weeks (T2), 36–40 weeks (T3), and one month postpartum (T4). Results: The IG had significantly higher exercise self-efficacy scores from T1 to T3 compared to the CG. IG participants showed notable progress in exercise behavior stages, transitioning from the contemplation stage at T1 to preparation and action stages at T2 (χ² = 13.208, p < 0.01), with some reaching the maintenance stage by T3 (20.9%, χ² = 9.49, p < 0.05). In contrast, most of the CG participants remained at the contemplation stage throughout pregnancy to early postpartum. Linking Evidence to Action: The peer-led walking intervention with mHealth has the potential to enhance self-efficacy and promote sustained exercise behavior of women with overweight or obesity during and after pregnancy and is a valuable approach to establishing long-term exercise behavior. Trial Registration: ClinicalTrials.gov: NCT 05022680.