Maternal sleep duration and neonatal birth weight: the Japan Environment and Children’s Study

Abstract

Background The adequate maternal sleep duration required for favorable obstetric outcomes is unknown. We evaluated the association between maternal sleep duration and low birth weight infants, small for gestational age infants, and macrosomia. Methods Participants enrolled in the Japan Environment and Children’s Study, a nationwide birth cohort study, with singleton pregnancies after 22 weeks, who gave birth between 2011 and 2014 were enrolled and categorized into five groups according to maternal sleep duration during pregnancy: < 6.0 h, 6.0–7.9 h, 8.0–8.9 h, 9.0–9.9 h, and 10.0–12.0 h. We evaluated the association between maternal sleep duration and the incidence of low birth weight infants (< 2500 g), very low birth weight infants (< 1500 g), small for gestational age infants, and macrosomia (> 4000 g), with women with maternal sleep duration of 6.0–7.9 h as the reference, using a multiple logistic regression model. Results In total, 82,171 participants were analyzed. The adjusted odds ratios (95% confidence intervals) for low birth weight infants in women with maternal sleep duration of 9.0–9.9 h and 10.0–12.0 h and for small for gestational age infants in women with maternal sleep duration of 9.0–9.9 h were 0.90 (0.83–0.99), 0.86 (0.76–0.99), and 0.91 (0.82–0.99), respectively, before adjusting for excessive gestational weight gain. No significant association was observed between maternal sleep duration and these outcomes after adjusting for excessive gestational weight gain. Among women with appropriate gestational weight gain, the adjusted odds ratios (95% confidence intervals) for low birth weight infants and for small for gestational age infants with sleep duration of 9.0–9.9 h were 0.88 (0.80–0.97) and 0.87 (0.78–0.97), respectively. Conclusions Maternal sleep duration of 9.0–9.9 h was significantly associated with the decreased incidence of low birth weight infants and small for gestational age infants in pregnant women with appropriate gestational weight gain, compared with that of 6.0–7.9 h. Care providers should provide proper counseling regarding the association between maternal sleep duration and neonatal birth weight and suggest comprehensive maternal lifestyle modifications to prevent low birth weight and small for gestational age infants.

Urinary 8-hydroxy-2′-deoxyguanosine levels and small-for-gestational age infants: a prospective cohort study from the Japan Environment and Children’s Study

“…As described in our previous study, 1 the current analysis used the data set released in 2019 (data set: jecs-ta-20190930). Specifically, we used three types of data: (1) M-T1, obtained from a self-report questionnaire that was collected during the first trimester (the first questionnaire) and that included questions regarding maternal medical background, (2) M-T2, obtained from a self-report questionnaire that was collected during the second or third trimester (second questionnaire) and that included questions regarding partner lifestyle and socioeconomic status and (3) Dr-T1 and Dr-0m, which were collected from the medical record transcripts provided by each participant’s cooperating healthcare centre and that included data on obstetrical outcomes during the first, second and third trimesters, such as gestational age and birth weight.…”

“…As described in our previous study, 1 maternal participants were requested to provide information about their smoking status by choosing one of the following: ‘currently smoking’, ‘never smoked’, ‘previously did, but quit before realising current pregnancy’ and ‘previously did, but quit after realising current pregnancy’. Participants who chose ‘currently smoking’ comprised the smoking category, whereas other participants comprised the non-smoking category.…”

“…Self-administered questionnaires, which were completed by the women during the first trimester and second/third trimester, were used to collect information on demographic factors, medical and obstetric history, physical and mental health, lifestyle, occupation, environmental exposure at home and in the workplace, housing conditions and socioeconomic status. 19 20 As described in our previous study, 1 the current analysis used the data set released in 2019 (data set: jecsta-20190930). Specifically, we used three types of data:…”

“…We used a complete case analysis; there were no significant differences in participants' characteristics between those included in and excluded from the study (data not shown), as reported in our previous study. 1 Exposure U8-OHdG levels were measured from a urine sample collected once during pregnancy using liquid chromatography-tandem mass spectrometry at a single centre, the method of which has been reported elsewhere. 21 Although urine sampling for U8-OHdG assessment was planned for the second or third trimester in the JECS, there were differences in the actual measurement time points (median, 27.0 weeks of gestation; quartiles at 25.0, 27.0 and 29.0 weeks of gestation).…”

Sleep Disorders in Pregnancy

“…Reduced maternal sleep duration tends to be associated with lower birth weight [36]. Indeed, LBW incidence appears to be lower among sons/daughters born from women who sleep 9-9.9 hours every night, than among those women sleeping 6-7.9 hours [37]. Sleep deprivation during pregnancy is associated with longer labour during childbirth, lower pain threshold and discomfort, higher caesarean section rates, and preterm delivery [36].…”