Background: The contribution of maternal postnatal depression to infant growth and under-nutrition in Africa has not been well studied. This study aims to examine the impact of postnatal depression (PND) on infants' physical growth in the first 9 months of life in Nigeria.
Methods: A longitudinal case controlled study in which 242 women (consisting of 120 depressed and 122 matched non-depressed postpartum women) had their infants' weight and length measured at the 6th week, 3rd month, 6th month and 9th month after delivery. Discontinuation with breastfeeding and illnesses like diarrhoea, persistent vomiting, fever and cough were also recorded at these periods.
Results: Infants of depressed mothers had statistically significant poorer growth than infants of non-depressed mothers at the 3rd month (weight OR 3.41, 95% CI 1.30-8.52; length OR 3.28, 95% CI 1.03-10.47) and the 6th month postpartum (weight OR 4.21, 95% CI 1.36-13.20; length OR 3.34, 95% CI 1.18-9.52). Depressed mothers were more likely to stop breastfeeding earlier and their infants more likely to have episodes of diarrhoea and other infectious illnesses.
Limitations: Psychiatric interview was conducted only once (at 6 weeks postpartum), our sample size was moderate and we did not account for mothers who had been depressed in pregnancy.
Conclusion: Prevention of postnatal depression and close monitoring of the growth of infants of depressed mothers should be integrated into maternal and child health policies in this region.