Breastfeeding and child cognitive outcomes: Evidence from a hospital-based breastfeeding support policy

This paper estimates the causal effects of breastfeeding on early child development using exogenous variation in breastfeeding support policies across UK maternity hospitals. Based on data from the Millennium Cohort Study, we find that mothers giving birth in hospitals where such policies are implemented are between 8 and 9 percentage points more likely to breastfeed exclusively at 4 and 8 weeks than mothers who give birth in other hospitals. The effect of breastfeeding are found to be large and positive on many different measures of child cognitive development throughout early childhood. In contrast to the previous literature, we find no statistically significant impact of breastfeeding on a number of health outcomes, but we see an improvement in child emotional development and maternal mental health.