Pregnancy Exercise and Nutrition With Smartphone Application Support: A Randomized Controlled Trial

To evaluate the effect of a healthy lifestyle package (an antenatal behavior change intervention supported by smartphone application technology) on the incidence of gestational diabetes mellitus (GDM) in overweight and obese women.

Women with body mass indexes (BMIs) 25-39.9 were enrolled into this randomized controlled trial. The intervention consisted of specific dietary and exercise advice that addressed behavior change supported by a tailor-designed smartphone application. Women in the control group received usual care. The primary outcome was the incidence of GDM at 28-30 weeks of gestation. To reduce GDM from 15% to 7.2%, we estimated that 506 women would be required to have 80% power to detect this effect size at a significance of .05, that is, 253 in each group.

Between March 2013 and February 2016, 565 women were recruited with a mean BMI of 29.3 and mean gestational age of 15.5 weeks. The incidence of GDM did not differ between the two groups, 37 of 241 (15.4%) in the intervention group compared with 36 of 257 (14.1%) in the control group (relative risk 1.1, 95% CI 0.71-1.66, P=.71).

A mobile health-supported behavioral intervention did not decrease the incidence of GDM.

ISRCTN registry, https://www.isrctn.com/, ISRCTN29316280.