Poor sleep maintenance and subjective sleep quality are associated with postpartum maternal depression symptom severity

Women are at increased risk of developing mood disorders during the postpartum period, and poor postpartum sleep may be a modifiable risk factor for the development of depression. This longitudinal study investigated the relationship between sleep variables and postpartum depression symptoms using wrist actigraphy and self-report surveys. Twenty-five healthy primiparous women were recruited from their outpatient obstetricians' offices from July 2009 through March 2010. Subjects wore wrist actigraphs for 1 week during the third trimester of pregnancy and again during the 2nd, 6th, 10th, and 14th weeks postpartum while completing sleep logs and sleep surveys. Subjective assessments of mood were collected at the end of each actigraph week. Subjective sleep assessments were strongly predictive of depression severity scores as measured by the Edinburgh Postnatal Depression Scale (EPDS) across all weeks (p < 0.001). Actigraphic measures of sleep maintenance, such as sleep fragmentation, sleep efficiency, and wake time after sleep onset, were also significantly correlated with EPDS scores postpartum. However, there was no relationship between nocturnal sleep duration and EPDS scores. This study provides additional evidence that poor sleep maintenance as measured by wrist actigraphy, rather than lesser amounts of sleep, is associated with EPDS scores during the postpartum period and that subjective assessments of sleep may be more accurate predictors of postpartum depression symptoms than wrist actigraphy. It also supports the hypothesis that disrupted sleep may contribute to the development and extent of postpartum depression symptoms.