Background: Children s weight has increased sharply in recent years. This may put them at higher risk for health problems. High blood glucose in a pregnant mother and too much weight gain during pregnancy also may have long-term effects on the child s health. Children who become overweight or obese during childhood tend to remain so as adults. Researchers want to study many risk factors during and after pregnancy, and how these affect a child s development. They will also follow the mother s health and well-being after pregnancy. Objectives: To learn how a pregnant mother s environment, lifestyle, and health conditions may affect her child s growth and development from birth until adulthood. Eligibility: American Indian/Alaska Native (AI/AN) or Hispanic adult pregnant women and their offspring. Design: Mothers will have 3 visits during pregnancy. In the child s first year, mothers will have 2 visits and their child will have 4. Children will have 2 visits in their second year and 1 each year until they turn 18. Mothers will have a visit 2 years after birth and 4-5 years later. Both the mother and child s medical records will be reviewed. They will have physical exams and give blood and stool samples. Mothers may give cord blood and placenta samples. They will give breastmilk and urine samples. They will fill out questionnaires. They will have an ultrasound. They may get an activity monitor. Mother and child will be followed until the child s 18th birthday. ...