The impacts of insufficient sleep and its change during pregnancy on postpartum depression: A prospective cohort study of Korean women.

OBJECTIVE To determine the association between insufficient sleep in the prenatal period and postpartum depression (PPD), and whether changes in sleep patterns during pregnancy increase the risk of PPD. METHODS A prospective cohort study was conducted between March 2013 and November 2017. Participants completed a sleep questionnaire pre-pregnancy and at 12, 24 and 36 gestational weeks (GW). Depressive symptoms were assessed by the Edinburgh Postnatal Depression Scale (EPDS) at 4 weeks postpartum, and the cut-off score for PPD was 10 or more. RESULTS Of 2512 participants, 410 (16.3%) were identified as having PPD. Only insufficient sleep at 36 GW was significantly associated with PPD after adjusting for confounding factors (odds ratio 1.79, 95% confidence interval 1.40-2.27, P < 0.001). Both Group 1 (change from sufficient to insufficient) and Group 3 (sustained insufficient) demonstrated a significant risk of PPD at all starting time-points in the multivariate analysis, but no significant association was evident between Group 2 (change from insufficient to sufficient) and PPD. CONCLUSION Insufficient sleep at 36 GW was associated with a significant risk of developing PPD. Additionally, regardless of whether women had sufficient sleep, a shift towards worsening sleep at 36 GW was highly associated with PPD.