Breast feeding.
D000818:Animals; D001721:Birth Intervals; D001940:Breast / Q000502:physiology; D001942:Breast Feeding; D003906:Developing Countries; D005260:Female; D006801:Humans; D007225:Infant Food; D007231:Infant, Newborn; D007774:Lactation; D008895:Milk, Human / Q000502:physiology; D010053:Ovary / Q000502:physiology; D011247:Pregnancy; D013391:Sucking Behavior / Q000502:physiology