Postnatal depression is a recognised cause of delayed cognitive development in infants in developed countries. Being underweight is common in South Asia.Study provides evidence for the first time that postnatal depression, a potentially treatable disorder, is a cause of poor growth and development in South Asia. Postnatal depression (PND) is a psychological disorder which occurs within six weeks after childbirth. It is a serious mental health problem for women and its consequences have important implications for the welfare of the family and the development of the child.1 A meta-analysis has shown an average prevalence of 13% (95% CI 12.3 to 13.4).2 There is a large, and compelling body of evidence implicating PND with adverse child development outcomes, particularly cognitive development.3,4 All the published literature on the impact of PND on infant development is from developed countries.

Two hypotheses were tested in this study. First, we wished to replicate the well known association between PND and development in the setting of a low income country. Second, we wished to test the hypothesis that PND in the mother at 6–8 weeks after childbirth is a risk factor for poor growth outcomes at 6 months. The rationale behind the hypothesis is that if PND is linked to adverse developmental outcomes, it could be a risk factor for poor growth in developing countries where awareness of mental health problems is low and rates of undernutrition high. This would be especially relevant in regions like Goa which have relatively better economic standards relative to other states in India, but continue to experience persistently high levels of undernutrition.