Risk Factors for Antenatal Depression and Associations with Infant Birth Outcomes: Results From a South African Birth Cohort Study

Abstract

Background: Maternal antenatal depression may be particularly prevalent in low- and middle-income countries, but there is a paucity of data on its effect on birth outcomes in such settings. We investigated risk factors for antenatal depression and the associations between depression and infant birth outcomes in the Drakenstein Child Health Study (DCHS), a birth cohort study in the Western Cape, South Africa.

Methods: The prevalence of depression in pregnant women enrolled in the DCHS from primary care antenatal clinics was measured using the Beck Depression Inventory (BDI-II). Predictors of antenatal depression were investigated using logistic regression, and the associations between depression and infant birth outcomes were examined in linear regression models.

Results: Among 726 pregnant women (median age: 26 years), 156 (21%) had BDI-II scores suggesting depression. Independent predictors of depression included single marital status, low socioeconomic status (SES), recent stressful life events, unplanned pregnancy, childhood trauma, and past-year intimate partner violence. No association was observed between antenatal depression and preterm birth. Strong associations were observed between antenatal depression and decreased infant weight-for-age (WAZ) and head circumference-for-age (HCAZ) z-scores at birth. In multivariable analysis, the association between depression and decreased HCAZ remained significant, when adjusted for clinic, SES, and recent stressful life events.

Conclusions: Antenatal depression and associated risk factors are highly prevalent in this setting and are associated with adverse fetal growth. Maternal mental health may be an important predictor of infant growth in utero.

Keywords: South Africa; antenatal depression; fetal growth.