Effect of physical activity and/or healthy eating on GDM risk: The DALI Lifestyle Study

CONTEXT: Lifestyle approaches for preventing gestational diabetes mellitus (GDM) have produced mixed results.

OBJECTIVE: The aim of this study was to compare the effectiveness of three lifestyle interventions (Healthy eating (HE), Physical activity (PA) and both HE and PA (HE+PA)) with usual care (UC) in reducing GDM risk.

DESIGN: Multicentre Randomised Controlled Trial 2012-2014: The Dali Lifestyle Study Setting: Antenatal clinics across 11 centres in 9 European countries Patients: Consecutive pregnant women <20 weeks gestation with a BMI≥29 kg/m(2) and without GDM by IADPSG criteria (n=436).

INTERVENTION: Women were randomized, stratified by site, to Control, HE, PA or HE+PA. Women received 5 face-to-face and up to 4 telephone coaching sessions, based on the principles of motivational interviewing. Gestational weight gain (GWG) <5kg was targeted. Coaches received standardized training and an intervention toolkit tailored to their culture/language.

MAIN OUTCOME MEASURES: GWG at 35-37 weeks, fasting glucose and insulin sensitivity (HOMA-IR) at 24-28 weeks.

RESULTS: We randomized 108 women to HE&PA, 113 to HE, 110 to PA and 105 to UC. In the HE+PA group, but not HE or PA alone, women achieved substantially less GWG than controls by 35-37 weeks (-2.02 (95% CI -3.58; -0.46 kg). Despite this reduction there were no improvements in fasting or post-load glucose or,insulin concentrations or HOMA-IR. Birthweight, large and small for gestational age rates were similar.

CONCLUSIONS: The combined HE+PA intervention was able to limit GWG but did not reduce fasting glycaemia. Lifestyle change alone is unlikely to prevent GDM among women with a BMI≥29 kg/m(2).