Preconception health — that is, the health of people during their reproductive years — can influence babies’ health, too.

Growing evidence suggests that drug use, smoking, nutrition, and other lifestyle conditions can affect germ cells — sperm and egg — with consequences after fertilization. For example, maternal smoking is associated with increased risk of heart disease in children starting from birth, and paternal smoking is associated with type 2 diabetes in kids. However, only a few studies have reported associations between parental germ cells' exposure to environmental chemicals and diseases in children.

The NIEHS preconception program uses animal models and human studies to investigate whether germ cells' exposure to environmental chemicals before fertilization can be linked to observable changes in offspring.