Pregnancy as a period of change for household nutrition

Pregnancy is a time in which individuals change their health behaviours, bolstered by extensive public health guidance and growing evidence that a healthy prenatal environment fosters child development with lifelong benefits. We provide evidence on the dynamics of food purchases and nutritional quality during pregnancy and immediately after childbirth. Using household scanner data, we employ an event study approach and show that households substantially change their shopping behaviour. They buy 20% more calories towards the end of pregnancy relative to pre-pregnancy, with calories remaining 8% higher three months after birth. While households follow guidelines to increase fruit and decrease alcohol, we find a substantial deterioration of the overall nutritional quality of purchases, driven by sustained increases in foods high in saturated fat, sugar and salt, substitution away from protein-rich foods, and a large (temporary) increase.