Association of maternal nocturnal sleep throughout pregnancy with the early nocturnal sleep of infants

Abstract

Objective: To investigate the association between maternal nocturnal sleep during pregnancy and their infants' nocturnal sleep patterns in early infancy by establishing a birth cohort. Methods: In this prospective study,healthy pregnant women and their infants were recruited in Chongqing Health Center for Women and Children from September 2013 to January 2014. A total of 40 healthy pregnant women and their infants were enrolled, and 34 pairs (85%) completed the whole survey. Actiwatch, wearing on the mother's wrist or infant's ankle,was used to monitor nighttime sleep at home for 7 times in total,with 7 consecutive days for each monitoring course. Pregnant women were monitored at 16, 24, 32 weeks gestational age, and were required to finish Pittsburgh Sleep Quality Index (PSQI) scale at the end of each monitoring. Their infants were initially monitored at 14 days after birth, followed by 1(st), 2(nd), and 3(rd) month after birth,with sleep diary recorded by parents. Pearson correlation analysis and multivariate linear regression were used to investigate the potential correlation between these two sleep patterns. Results: The average nocturnal sleep time was (465±53) min throughout pregnancy, with increased trend in the latency of maternal nighttime sleep onset ((30±15), (34±29), (38±30) min) while decreasing of average sleep efficiency ((85±5)%, (84±8)%, (83±8)%). The longest night sleep duration decreased from (382±74) min in the first trimester to (330±83) min in the third trimester (F=4.932, P<0.05), while awakening time after sleep onset (WASO) correspondingly increased from (27±22) min to (53±25) min (F=12.605, P<0.05). In terms of infants, the latency of nighttime sleep onset decreased from (43±33) min on the 14th day to (20±29) min at 3-month of age (t=3.281, P=0.002), while the longest nighttime sleep duration increased from (20±62) min to (265±140) min (t=3.867, P<0.01); meanwhile, the total nocturnal sleep time and the sleep efficiency increased from (373±126) min and (63±28)% to (431±103) min and (75±16)%, respectively (t=2.362, P=0.024; t=2.418, P=0.039, respectively). After adjusting for maternal age and body mass index (BMI), parental educational level and family income, maternal mood, exposure to tobacco and alcohol during pregnancy, method of delivery, as well as infants' gender, feeding patterns and gestational weeks, the regression analysis showed that the total nocturnal sleep time and the longest nighttime sleep duration during pregnancy were positively correlated with the corresponding parameters of their infants at the age of 3 months (B=0.541, 95%CI 0.168-0.914, t=2.882, P=0.005; B=0.310, 95%CI 0.035-0.586, t=2.240, P=0.027, respectively). Conclusions: The total nocturnal sleep time and the longest nighttime sleep duration during pregnancy are positively correlated with the corresponding parameters of their infants in early infancy. Paying more attention to improve maternal sleep quality may facilitate their infants to establish sleep-wake patterns early.