272 Family Planning Perspectives

Sexual intercourse at young ages isquite common in the United States:Eighty-one percent of women aged 20–24 had sexual intercourse before they w e re 20.1 Although sexual activity before age 20 and before marriage has become the norm in developed countries,2 p re g-nancy and childbearing among adoles-cents are seen by many as disadvanta-geous to both the individuals involved and society, and numerous programs at-tempt to reduce pregnancy rates among adolescents by encouraging abstinence and contraceptive use. It is therefore im-portant to track trends in pregnancy rates, birthrates and abortion rates among teen-agers (i.e., 15–19-year-olds) at both the na-tional and the state levels. Accurate birth data are collected and published by the National Center for Health Statistics (NCHS) of the U.S. De