Sleepiness in pregnancy and adverse perinatal outcomes

Sleep disorders in pregnancy have been associated with adverse pregnancy outcomes including hypertensive disorders of pregnancy, preterm birth, and gestational diabetes mellitus, yet these findings are largely from retrospective studies. Using data from a prospective study that used validated tools to assess sleepiness in pregnancy, we aimed to assess the association of sleepiness in pregnancy with adverse pregnancy outcomes.

In this secondary analysis of data from a large, diverse prospective cohort of nulliparous individuals conducted at eight United States medical centers, those with self-reported sleep data were included. Sleepiness was evaluated in early (6-13 weeks) and mid-pregnancy (22-29 weeks) via the Epworth Sleepiness Scale, a validated tool to assess daytime sleep propensity (i.e., the ability to fall and stay asleep). Those with scores ≤10 were categorized as having no sleepiness (referent), 11-15 moderate sleepiness, and 16-24 severe sleepiness. The outcomes were hypertensive disorders of pregnancy, gestational diabetes, preterm birth, and small-for-gestational-age birth < 10 percentile. Multivariable logistic regression analysis adjusting for multiple potential confounders was performed to evaluate the associations of moderate and severe sleepiness with each outcome.

Of 6806 eligible participants who completed daytime sleepiness questionnaires at both time points, the mean score in early and mid-pregnancy was 7.8 (standard deviation 4.1) and 6.5 (standard deviation 4.0), respectively. In early pregnancy, 20.0% and 4.3% of people reported moderate and severe daytime sleepiness, respectively; in mid-pregnancy, 14.4% and 2.5% of people experienced moderate and severe sleepiness. Severe sleepiness in mid-pregnancy was associated with gestational diabetes (7.1% severe sleepiness vs. 3.8% no sleepiness; adjusted odds ratio [aOR], 1.78; 95% confidence interval [CI], 1.01-3.12) and small-for-gestational-age birth (14.8% severe sleepiness vs. 10.3% no sleepiness; aOR, 1.35; 95% CI, 1.06-1.71).

Severe daytime sleepiness during mid-pregnancy, a symptom reflective of sleep quality, length, and often sleep disordered breathing, is associated with gestational diabetes and small-for-gestational-age birth, suggesting a potential relationship with maternal glucose metabolism and placental function.