Impact of an mHealth-supported behavioural lifestyle intervention on exercise stage-of-change and physical activity in overweight and obese pregnancy: pEARs randomised controlled trial (RCT)

Introduction Regular physical activity (PA) could improve obstetric outcomes among overweight and obese pregnant women. However, overweight and obese women report barriers to increasing PA. Mobile health (mHealth) technologies could support antenatal lifestyle interventions to improve PA, though further research is needed. We investigated the influence of an mHealth‐supported lifestyle intervention on exercise stageof‐ change and PA among overweight and obese pregnant women. Methods This is an RCT of 565 women (BMI 25‐39.9 kg/m2), randomised in early pregnancy to standard care (n = 287) or a healthy lifestyle package (n = 278) involving in‐person nutrition and exercise advice, supported by a smartphone app. At 15 and 28 weeks of gestation, exercise stage‐of‐change score (1‐5), which indicates readiness to change PA behaviours, and PA were measured using validated questionnaires. Results At baseline, there were no significant differences between intervention and control groups for demographics, stage‐ofchange score and PA. The proportion of women at stage 5 (maintenance stage, indicating regular participation in PA) did not differ between intervention and control groups (32.4% versus 33.3%). The intervention group had significantly higher PA at 28 weeks (in METs per week; P < 0.001) and a greater proportion of women meeting ACOG PA recommendations (27.1% versus 15.5%; P = 0.02). A higher proportion of the intervention group maintained or increased stage‐of‐change score (90.3% versus 72.7%; P < 0.001), and were at stage‐5 (56.0% versus 32.9%; P < 0.001). An mHealth‐supported intervention assisted women with maintaining or improving readiness to change PA, and follow PA recommendations. These findings are significant for women that may benefit from consistent, easily‐accessible advice to assist behaviour‐change and improve PA during pregnancy.