Data on physical activity (PA) and the risk of gestational diabetes (GDM) are inconsistent. We examined whether physical activity (PA) during the first trimester of pregnancy was associated with glucose tolerance and GDM in women with overweight/obesity. Participants (n=261) were a subsample from the GestationaL Weight Gain and Optimal Wellness (GLOW) trial conducted at Kaiser Permanente Northern California in 2014-2016 to test whether a lifestyle intervention prevents excess gestational weight gain compared to usual care. Participants wore an ActiGraph wGT3X-BT accelerometer for 7 days on the non-dominant wrist to estimate mean daily minutes of moderate to vigorous intensity PA (MVPA), and completed a pregnancy PA questionnaire assessing sports and exercise activity. Plasma glucose values from random 50-g 1-hour glucose challenge tests (GCT) and GDM diagnosed by the Carpenter and Coustan thresholds for the 100-g, 3-hour oral glucose tolerance test were obtained from electronic health records. Associations with PA, by accelerometer and questionnaire (i.e., square root transformed), were estimated by linear and logistic regression models and adjusted for age, race-ethnicity, BMI category, and GLOW randomization (i.e., intervention vs. usual care). Participants had a median 38 minutes per day (IQR= 37) of MVPA by accelerometry and self-reported a median 9 MET hours per week (IQR= 14) of sports and exercise activity on the questionnaire, both assessed at mean 11 weeks’ (SD= 1.4) gestation. Median plasma glucose on the GCT performed at 24-28 weeks’ gestation was 112 mg/dl (IQR= 35); 14 participants (5.4%) developed GDM. Neither PA variable was statistically significantly associated with GCT glucose or GDM (p > .05). Objectively measured MVPA and self-reported sports and exercise activity assessed in the first trimester do not appear to impact glucose tolerance or GDM in women with overweight/obesity.


S.F. Ehrlich: None. M.M. Hedderson: None. S.D. Brown: None. S.E. Crouter: None. P. Hibbing: None. J. Feng: None. A. Tsai: None. A. Ferrara: None.


National Institutes of Health (K01DK105106)

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