Maternal sleep-disordered breathing and sleep disruption possess adverse effects on pregnancy outcomes via numerous potential pathophysiologic pathways. A recent study hypothesized that disordered maternal sleep also adversely impacts the neuromaturation of the fetus.This study included 102 obese pregnant women (pre-pregnancy body mass index [BMI] of 30 or higher) at 36 weeks of pregnancy. It quantified fetal neuromaturation, expressed via measures of fetal heart rate variability, motor activity, and motor-cardiac coupling, through digitized fetal actocardiography during an afternoon recording, and collected maternal sleep measures overnight through polysomnography. Data were analyzed using multiple regression, with maternal BMI, blood pressure, and diabetes taken into account.The results were as follows:Indicators of higher sleep-disordered breathing showed an association with delayed fetal neuromaturation and greater fetal motor activity. Less maternal sleep disruption (shorter rapid eye movement [REM] latency, more REM sleep, and/or fewer transitions) showed an association with higher fetal heart rate variability and coupling-based neuromaturation.Thus, the features of disordered maternal sleep influence the developing fetal nervous system. It is unknown if these results hold true for the non-obese population too. This topic is less explored, and further studies may describe effects that stay beyond pregnancy.Finally, it is evident that maternal sleep-disordered breathing and sleep disruption adversely affect fetal neuromaturation in pregnant women with obesity.DiPietro JA, Watson H, Raghunathan RS. et al. Fetal neuromaturation in late gestation is affected by maternal sleep disordered breathing and sleep disruption in pregnant women with obesity. International Journal of Obstetrics and Gynecology. 2022;157(1):181-187.