BackgroundPrenatal exposure to per- and polyfluoroalkyl substances (PFAS) may adversely affect fetal brain development, yet no study has investigated the potential association between prenatal PFAS exposure and infant sleep. ObjectivesTo explore the associations of prenatal PFAS exposure with infant sleep disturbances during the first year of life in a prospective cohort study. MethodsWe recruited 4127 pregnant women from the Shanghai Birth Cohort (SBC) and followed their children from birth to 12 months old. A total of 2366 infants were included in the 6-month analyses, and 2466 infants in the 12-month analyses. Ten PFAS were quantified in blood serum collected in the first trimester. Sleep quality was measured using the Brief Infant Sleep Questionnaire. We used multiple linear regression and multinomial logistic regression to estimate the individual effects of PFAS on sleep outcomes. We utilized a quantile-based g-computation model to determine the joint effects of the PFAS mixture on infant sleep outcomes. Additionally, generalized estimating equation (GEE) models were performed to examine the longitudinal effects of PFAS exposure during pregnancy. ResultsIn infants aged 6 months, perfluorooctane sulfonate and perfluoroheptanoic acid were associated with a more than 2-fold risk of parent-reported sleep problems as severe. Perfluorodecanoic acid was associated with an increased risk of often or almost always snoring in one-year-old infants (relative risk ratios, 1.79; 95% CI, 1.12–2.86). PFAS mixtures were positively associated with nighttime awakenings both among infants aged 6 months (β, 0.11; 95% CI, 0.04–0.19) and 12 months (β, 0.11; 95% CI, 0.05–0.18). Prenatal exposure to PFAS were associated with longer sleep latency, increased nighttime awakenings, longer nocturnal wakefulness hours, snoring, and earlier sleep-onset time in infants aged 6–12 months, according to GEE models. ConclusionsOur study suggests that prenatal exposure to PFAS may increase the risk of sleep disturbance in infants.