The impact of perinatal depression on exclusive breastfeeding: a cohort study.

Perinatal depression is associated with infant undernutrition. We hypothesised that perinatal depression was associated with early cessation of exclusive breastfeeding and reduced quantity of breast milk in rural Pakistan. We used a prospective cohort design to study a population-based sample of 132 depressed and 147 non-depressed women from the third trimester of pregnancy to 6 months post-natal. Current major depressive episode was measured in the third trimester and 6 months post-natal using the Structured Clinical Interview for DSM-IV Diagnosis. In a convenience sample of 24 depressed and 31 non-depressed exclusively breastfeeding mothers, breast milk quantity was assessed (mL kg(-1) infant weight per 24 h) at 4 months using the dose-to-mother deuterium dilution method. We administered also the Perception of Insufficient Milk questionnaire at 6 months post-natal. Depression was associated with fewer days of exclusive breastfeeding (91.8 (SD = 47.1) vs. 108.7 days (SD = 54.3) (95% CI: 3.4 to 30.3 P = 0.014). Women with persistent depression ceased exclusive breastfeed earliest. There was no difference in the quantity of breast milk produced by depressed and non-depressed mothers: 89.3 (SD = 38.1) vs. 83.9 (29.0) ml/kg infant wt/24 hours, P = 0.57. Depressed mothers were significantly more likely to report insufficient milk: PIM scores were 34.4 (SD = 14.3) for depressed and 39.7 (SD = 10.4) for non-depressed women (P = 0.004). In Cox regression PIM score mediated the association between depression and early cessation of breastfeeding. In this area of rural Pakistan, perinatal depression is associated with early cessation of exclusive breastfeeding and this is associated with mothers' perceptions of insufficiency of breast milk but not reduced milk production.