Does Maternal Depression Undermine Childhood Cognitive Development? Evidence from the Young Lives Survey in Peru

This paper studies the effect of maternal depression on early childhood cognition in Peru. The identification strategy exploits variation in exposure to exogenous shocks during early life to instrument for maternal depression. The results suggest that maternal depression is detrimental to the child's vocabulary at age five. Although the effects fade out by age eight, early vocabulary gaps can undermine other development outcomes. The effects do not vary by maternal education, but they are significant only for children living in disadvantaged households. The presence of a partner worsens the effect of maternal depression on vocabulary development, and this effect is driven by households with partners who drink heavily.