An overview of 50 years of research at the University of Southern California on how fathers influence children’s development during pregnancy has made several recommendations for public health services: Consider fathers’ health behaviors as well as mothers’, Assess and treat fathers’ mental health as well as mothers’, Treat family stress and attend to the couple’s relationship, and Provide access for fathers to family leave. Much research focuses on how mothers-to-be influence babies’ health and development before and during pregnancy—touching on mothers’ environments, emotions, and behaviors. Mothers-to-be are often advised to alter their lifestyles accordingly. Less attention is paid to fathers, but there is sufficient evidence to make a case for practice and policy to change in this regard. This research review sets out seven ways fathers influence children’s development during pregnancy, providing a useful tool for planners of prenatal services and policies. Epigenetic and genetic changes: Prior health behaviors Obesity …