Introduction
Neonatal birth weight, which is related to perinatal morbidity and
mortality,1–4 is affected by several obstetric
complications, including preterm births (PTB), fetal growth restriction
(FGR), and preeclampsia.5,6 Specifically, birth weight
<1,500 g, defined as very low birth weight, is affected by
severe prematurity and leads to increased mortality.7Additionally, small for gestational age (SGA) infants have also been
associated with neonatal and post-neonatal
mortality.4,8,9 Further, LBW and SGA are associated
with increased risk of coronary artery disease, diabetes mellitus, and
arterial hypertension in adult life, as described in the Baker
hypothesis,10 which has been revised to the concept of
developmental origins of health and disease (DOHaD).11Conversely, macrosomia, defined as birth weight >4,000 g,
is also associated with a risk of morbidity in
infants.2,12
Several modifiable factors, including maternal pre-pregnancy body
weight, gestational maternal body weight gain (BWG), and diet, have a
major impact on the neonatal birth weight.5,12–14Similarly, maternal sleep duration (MSD) during pregnancy also affects
obstetric outcomes.15–17 However, the association
between MSD and neonatal birth weight remains
unclear.15,18 Previous studies have reported reduced
MSD as a risk factor for SGA,19,20 but Morokuma et al.
reported no association between MSD and SGA in a study including 8,631
participants.21 Moreover, the appropriate MSD required
to prevent LBW, SGA, and macrosomia has not been elucidated. As sleep is
often disturbed in pregnant women,15 appropriate MSD
would be a great concern for pregnant women.
The present study evaluated the effect of MSD on neonatal birth weight
using the data from a nationwide Japanese prospective birth cohort
study.