In comparison with other industrialized countries, the United States has exceptionally high rates of adolescent pregnancy and abortion. In 1999, nearly half of high-school students reported having had sexual intercourse, and 6 percent said they had been pregnant or gotten someone pregnant (CDC 2000). American adolescents are especially unlikely to use birth control, and those who do practice contraception tend to rely on inefficient methods (Forrest 1990).

Sexual behavior at first intercourse is of particular interest because early entry into sexual activity is associated with contraceptive nonuse and a heightened risk of pregnancy (Abma and Sonenstein 2001; Koenig and Zelnik 1982; Zabin, Kantner, and Zelnik 1979). Moreover, the timing of first intercourse may be a useful marker for risky sexual behavior and a history of sexually transmitted diseases (Greenberg, Magder, and Aral 1992). For example, age at first intercourse is inversely associated with the number of lifetime sexual partners (McGuire et al. 1992).

Data from the National Longitudinal Study of Adolescent Health (Add Health) were used to examine the impact of parents' behavior on adolescents' sexual experience and contraceptive use. All else being equal, adolescents whose parents engage in risky behaviors are especially likely to be sexually active and to have had sex before age 15. These findings are only partly attributable to the link between parents' risky behaviors (smoking, drinking, driving without seatbelts) and adolescents' risky behaviors (smoking, drinking, delinquent activity, association with substance-using peers). Although parental behaviors are effective predictors of adolescents' sexual activity, they are not effective predictors of contraceptive use or of method choice at first coitus. Overall, parents with low levels of self-efficacy seem to be especially likely to have children at risk of engaging in problem behaviors.