Associations of physical activity and sedentary behavior during pregnancy with gestational diabetes mellitus among Asian women in Singapore

Background: Few studies have investigated physical activity (PA) and sedentary behavior (SB) in relation to fasting (FG) and 2-h postprandial plasma glucose (2hPG) levels and gestational diabetes mellitus (GDM); we investigated these associations among Asian pregnant women. Methods: As part of the Growing Up in Singapore Towards healthy Outcomes cohort study, PA and SB (sitting and television times) were assessed by interviewer-administered questionnaire. During 75 g oral glucose tolerance tests at 26-28 weeks' gestation we measured FG, 2hPG levels and GDM (FG >= 7.0 mmol/L and/or 2hPG >= 7.8 mmol/L). Associations were analysed by multiple linear and logistic regression. Results: Among the 1083 women studied, 18.6% had GDM. SB was not associated with FG, 2hPG and GDM. Higher categories of PA were associated with lower 2hPG and a lower likelihood of GDM (p-trend < 0.05), but not with FG levels. Compared to insufficiently active women, highly active women had lower 2hPG levels [beta (95% CI): -0.32 (-0. 59, -0.05), p = 0.020) and were less likely to have GDM [OR: 0.56 (0.32-0.98), p = 0.040]. Stratified analysis revealed no associations among under/normal-weight women, but significant associations among overweight/obese women; in those with BMI >= 23 kg/m(2), sufficiently active and highly active women were less likely to have GDM [OR: 0.52, (0.29-0.93), p = 0.028, and OR: 0.34, (0.15-0.77), p = 0.010, respectively]. Conclusion: Higher PA was associated with lower 2hPG levels and a lower prevalence of GDM, particularly in overweight/obese women. Further studies are warranted to confirm these findings, and to examine the effectiveness of PA promotion strategies for the prevention of gestational hyperglycemia.