In mammalian physiology, lactation follows pregnancy, and disruption of this physiology is associated with adverse health outcomes for mother and child. Although lactation is the physiologic norm, cultural norms for infant feeding have changed dramatically over the past century. Breastfeeding initiation fell from 70% in the early 1900s to 22% in 1972. In the past 40 years, rates have risen substantially, to 77% in 2010. Although more mothers are initiating breastfeeding, many report that they do not continue as long as they desire. As reproductive health care experts, obstetricians are uniquely positioned to assist women to make an informed feeding decision, offer anticipatory guidance, support normal lactation physiology, and evaluate and treat breastfeeding complications. Integration of care among the obstetrician, pediatric provider, and lactation consultant may enable more women to achieve their breastfeeding goals, thereby improving health outcomes across two generations.