Dynamic Associations Among Infant Sleep Duration, Maternal Sleep Quality and Postpartum Mood Symptoms

An increase in negative mood is common during the postpartum period. Two related but distinct factors can increase their risk: infant sleep duration and maternal sleep quality. This study evaluated the dynamic interplay among infant sleep duration, maternal sleep quality, and symptoms of postpartum depression and anxiety. This prospective observational pilot study included pregnant women (N = 168) aged 18-45 years, with a history of depression. Maternal sleep quality, mood symptoms, and infant sleep duration were collected monthly after delivery up to 6 months postpartum. Random intercept cross-lagged panel models (RI-CLPMs) were used to examine the stability and reciprocal relationships over the first 6 months. Separate RI-CLPMs were run for maternal postpartum depression and maternal anxiety (i.e., two RI-CLPMs with infant sleep duration, maternal sleep quality, and the respective maternal mood variable). Infant sleep was only associated with maternal sleep in the first month postpartum. At month 4, better infant sleep was associated with lower levels of maternal depression and anxiety. Maternal sleep problems significantly and positively predicted postpartum depression and anxiety at the subsequent month (b = 0.21 (SE = 0.07), p = 0.005; b = 0.32 (SE = 0.09), p < 0.001, respectively). Findings support previous research that maternal-infant sleep is most strongly coupled in early postpartum, whereas the link between maternal sleep quality and postpartum mood symptoms is persistent across 6 months postpartum. Infant sleep was variably associated with postpartum mood symptoms. Interventions need to address both maternal and infant sleep.