Maternal mood symptoms in pregnancy and postpartum depression: association with exclusive breastfeeding in a population-based birth cohort

This study aimed to evaluate the association between mood symptoms during pregnancy and exclusive breastfeeding at 3 months, as well as the association between exclusive breastfeeding at 3 months and maternal depression at 12 months postpartum.

Data from the Pelotas 2004 Birth Cohort with 4231 live births were used. Maternal mood symptoms during pregnancy were assessed through the question "During pregnancy, did you have depression or nervous problems?" and depression symptomatology at 12 months postpartum was assessed with the Edinburg Postnatal Depression Scale (EPDS). Information on exclusive breastfeeding at 3 months was collected through a dietary recall questionnaire. Crude and adjusted relative risks (RR) with 95% confidence intervals (95% CI) were estimated by Poisson regression.

Prevalence of mood symptoms during pregnancy was 25.1% (95% CI 23.8; 26.4%) and prevalence of EPDS ≥ 10 at 12 months after birth was 27.6% (95% CI 26.2; 29.0%). Prevalence of exclusive breastfeeding at 3 months was 26.5% (95% CI 25.2; 27.9%). In crude analyses, maternal mood symptoms during pregnancy were associated with non-exclusive breastfeeding at 3 months and non-exclusive breastfeeding at 3 months was associated with postpartum maternal depression at 12 months. In the adjusted analyses, both associations were lost after the inclusion of maternal education (RR 0.92; 95% CI 0.81-1.04 and RR 0.92; 95% CI 0.81-1.03, respectively).

In our study, the crude association between mood symptoms in pregnancy, exclusive breastfeeding at 3 months, and postpartum depression was due more to the low maternal education than to a true relationship between them.