A longitudinal study of sleep duration in pregnancy and subsequent risk of gestational diabetes: findings from a prospective, multiracial cohort

Background Both short and prolonged sleep duration have been linked to impaired glucose metabolism. Sleep patterns change during pregnancy, but prospective data are limited on their relation to gestational diabetes. Objective We sought to prospectively examine the trimester-specific (first and second trimester) association between typical sleep duration in pregnancy and subsequent risk of gestational diabetes, as well as the influence of compensatory daytime napping on this association. Study Design In the prospective, multiracial Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies-Singleton Cohort, 2581 pregnant women reported their typical sleep duration and napping frequency in the first and second trimesters. Diagnosis of gestational diabetes (n = 107; 4.1%) was based on medical records review. Adjusted relative risks with 95% confidence intervals for gestational diabetes were estimated with Poisson regression, adjusting for demographics, prepregnancy body mass index, and other risk factors. Results From the first and second trimester, sleep duration and napping frequency declined. Sleeping duration in the second but not first trimester was significantly related to risk of gestational diabetes. The association between second-trimester sleep and gestational diabetes differed by prepregnancy obesity status ( P for interaction = .04). Among nonobese but not obese women, both sleeping >8-9 hours or