A smartphone coaching program ("Bouge Grossesse") improves daily physical activity in pregnant women.

Background: Physical activity has been shown to reduce obstetrical risks however pregnant women reduce their physical activity and sedentary behaviors increase.

Objective: Our aim was to evaluate the impact of a smartphone application developed to increase daily physical activity in pregnant women.

Methods: We enrolled 250 pregnant women in a prospective randomized controlled study. These women were instructed to download either an intervention application called «Bouge Grossesse» (coaching program and a pedometer; n=125) or a Placebo application (pedometer only; n=125). Primary outcome was defined as a daily increase of 2000 steps/day between day 1 and day 90 or 10 000 steps/week between week 1 and week 12. Data was analyzed with intention to treat. Secondary outcomes were the number of steps at week 12 and the evolution of quality of life measured by WHO score, EIFEL score and SPIEGEL scale, and on maternal and fetal outcomes.

Results: Patients were enrolled between August 2017 and February 2019. They were retrospectively registered after September 2018. We found a significant difference in the primary outcome between the two groups in favor of the intervention group (22.4% success vs 3.2% in the control group, P<.001) but only 43 women in the intervention group (34.4%) and 16 women in the placebo group (12.8%) completed the 12-week coaching program. There were no significant differences in the SPIEGEL, EIFEL and WHO scores. The mean number of daily steps at week 12 was significantly higher in the intervention group (6900.0 vs 4371.9, P<.001).

Conclusion: The mobile health intervention « Bouge Grossesse » significantly increased physical activity in pregnant women but we observed a high percentage of withdrawals from the 12-week program.

Trial registration: This clinical trial was registered under the number NCT03688087 ClinicalTrials.gov.