All women are at risk for depression during pregnancy and the postpartum period, and there is growing evidence to suggest that poor sleep during pregnancy and the postpartum period may be a risk factor for the development of perinatal depression. Undoubtedly the interplay between sleep and depressive symptoms is quite complex. Does sleep disruption cause depression? Or is sleep disturbance merely an early symptom of a depressive illness?

In a prospective cohort study from China, researchers examined 1152 pregnant women in order to assess the association between sleep quality assessed during the second trimester and risk of antenatal and postpartum depression.  Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) during pregnancy. The Pregnancy Pressure Scale (PPS) was used to assess levels of stress, and the Edinburgh Postnatal Depression Scale (EPDS) was used to assess depressive symptoms. 

Poor sleep quality (PSQI scores ?5) was associated with higher levels of stress during pregnancy (odds ratio [OR]: 2.60, 95% CI: 1.79, 3.77).  In addition, poor sleep quality predicted antenatal depression (OR: 3.42, 95% CI: 2.48, 4.72) and postpartum depression (OR: 2.40, 95% CI: 1.58, 3.64) after adjusting for maternal age, BMI, gestational age, smoking, educational level, household income and social support. 

This is one of the largest studies linking poor sleep quality with increased risk for perinatal depression.  Because sleep is assessed only during the second trimester, it is not possible to determine in this study if sleep disturbance leads to antenatal depression or if sleep disturbance is a symptom of depression.  While poor sleep quality during the second trimester also predicts risk for postpartum depression, it is possible that poor sleep quality during pregnancy increases the risk of antenatal depression and that antenatal depression increases risk for postpartum depression.

It is recommended that all women should be screened for depression and anxiety during pregnancy; however, we may not specifically ask about sleep or use a validated screening tool to assess sleep during pregnancy.  With regard to tools that are commonly used to screen for perinatal depression, question 7 on the EPDS (“I have been so unhappy that I have had difficulty sleeping…”) and question 3 of the PHQ-9 (“Trouble falling or staying asleep, or sleeping too much?”) ask about sleep problems; however, it is not clear how these questions correlate with more elaborate assessments like the PSQI.

We might not fully understand the interplay between sleep and perinatal depression, but we do know that certain techniques may be used to improve sleep quality, and there is evidence to suggest that certain interventions – using medication or non-pharmacologic strategies – can also reduce the risk and/or severity of postpartum depression.  Thus, assessing sleep quality in pregnant and postpartum women may be an important element in the prevention and treatment of perinatal depression.  

Ruta Nonacs, MD PhD

Gao M, Hu J, Yang L, Ding N, Wei X, Li L, Liu L, Ma Y, Wen D.  Association of sleep quality during pregnancy with stress and depression: a prospective birth cohort study in China.  BMC Pregnancy Childbirth. 2019 Nov 27;19(1):444. Free Article