In the contemporary developed world, life often begins and ends in a medical setting. Just a century ago, nearly all babies in the United States were born at home, but by the beginning of the 21st century, just over 98% of U.S. births took place in a hospital. In developing countries in Southeast Asia or sub-Saharan Africa, where there is less access to health care and unattended home births are common, still approximately 20–30% of women deliver in a hospital, attended by an obstetric specialist on a labor and delivery (L&D) floor. This entry describes clinical areas in established medical institutions and how they affect individuals across the life span, following a chronological order from L&D at birth to primary care offices to acute care ...