Background There is a high prevalence of antepartum depression and low birth weight (LBW) in Bangladesh. In high- and low-income countries, prior evidence linking maternal depressive and anxiety symptoms with infant LBW is conflicting. There is no research on the association between maternal mental disorders and LBW in Bangladesh. This study investigates the independent effect of maternal antepartum depressive and anxiety symptoms on infant LBW among women in rural Bangladesh.

Methods A population-based sample of 720 pregnant women from two rural subdistricts was assessed for symptoms of antepartum depression, using the Edinburgh Postpartum Depression Scale, and antepartum anxiety, using the State Trait Anxiety Inventory, and followed for 6–8 months postpartum. Infant birth weight of 583 (81%) singleton live babies born at term (≥37 weeks of pregnancy) was measured within 48 h of delivery. Baseline data provided socioeconomic, anthropometric, reproductive, obstetric, and social support information.

Results After adjusting for potential confounders, depressive (OR 2.24; 95% CI 1.37 to 3.68) and anxiety (OR 2.08; 95% CI 1.30 to 3.25) symptoms were significantly associated with LBW (≤2.5 kg). Poverty, maternal malnutrition, and support during pregnancy were also associated with LBW.

Conclusions This study provides evidence that maternal depressive and anxiety symptoms during pregnancy predict the LBW of newborns and replicates results found in other South Asian countries. Policies aimed at the detection and effective management of depressive and anxiety symptoms during pregnancy may reduce the burden on mothers and act as an important measure in the prevention of LBW among offspring in Bangladesh.