Sleep Duration and Metabolic Biomarkers During Pregnancy: A Longitudinal Study in a Multiracial Cohort

Abstract Objective: To examine associations between sleep duration and metabolic biomarkers in pregnant women. Methods: This nested case-control study involved 321 pregnant women from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies-Singleton Cohort in the United States. Plasma metabolic biomarkers (glucose, insulin, C-peptide, and high-sensitivity C-reactive protein) were measured in blood samples obtained on visit 0 (10–14 gestational weeks (GWs)), visit 1 (15–26 GWs), and visit 2 (23–31 GWs). The homeostasis model assessment of insulin resistance was calculated at visit 1, when fasting glucose and insulin measurements were available. At each visit, structured questionnaires were used to assess habitual sleep durations (≤ 6 hours, 7–8 hours (reference), or ≥ 9 hours) since the previous visit. Associations between sleep duration and log-transformed metabolic biomarkers adjusted for maternal age, gestational week, race/ethnicity, education level, family diabetes history, pre-pregnancy body mass index, and physical activity were estimated using weighted generalized estimating equation models. Results: During visit 1, women who slept for ≥ 9 hours had significantly higher insulin levels when compared with those who habitually slept for 7–8 hours since the previous visit (adjusted β = 0.223, 95% confidence interval ( CI ): 0.020–0.425) and homeostasis model assessment of insulin resistance (adjusted β = 0.245, 95% CI : 0.025–0.465). At visit 2, glucose concentrations were significantly elevated in women with an average sleep duration of ≤ 6 hours since the previous visit (adjusted β = 0.152, 95% CI : 0.028–0.276). Conclusion: Both insufficient and excessive sleep during pregnancy were associated with unfavorable profiles of metabolic biomarkers. Therefore, further investigation of the role of sleep health in maternal metabolic risk is warranted.