As determined by the Center for Disease Control's epidemiologic surveillance of abortion mortality, the death-to-case rate for legal abortion in the United States for the three years 1972 to 1974 was 3.9/100,000 procedures. This mortality compares favorably with that from other commonly performed surgical procedures. Women who were older, were of nonwhite races, had the procedure in their state of residence, were at later gestational age, and who underwent intrauterine instillation or major abdominal surgery had the highest mortality. Duration of pregnancy proved to be the most important determinant of risk. Compared to mortality from pregnancy and childbirth, legal abortion in the first trimester was almost nine times safer.