We examined pregnancy rates and birth rates among United States teenagers aged 15 to 19 years in 1974, 1980, and 1983. Pregnancy rate refers to live births plus induced abortions per 1000 women; birth rate refers to live births per 1000 women. We present these rates for all teens aged 15 to 19 years and for teens aged 15 to 19 years who were sexually experienced. Data sources included National Center for Health Statistics birth records, Centers for Disease Control abortion surveillance reports, and Bureau of the Census population estimates. Sexual experience estimates came from national surveys of adolescent sexual behavior. Between 1974 and 1980, the pregnancy rate among all teens increased; the pregnancy rate among sexually experienced teens declined. From 1980 to 1983, the pregnancy rate declined among all teens and among sexually experienced teens. Birth rates among US teenagers (all teens and sexually experienced teens) declined between 1974 and 1983. Whereas the decline in the birth rate from 1974 to 1980 was primarily due to increased use of abortion, the decline from 1980 to 1983 related to the decrease in teenage pregnancies.