Substance use and other factors associated with risky sexual behavior among pregnant adolescents.

A study of the relationship between substance use and risky sexual behavior was conducted among 241 unmarried pregnant adolescents aged 17 and younger who lived in a metropolitan area in the Northwest. The respondents had comparable or higher lifetime use rates for all substances than did women in a national sample of high school seniors, even though the pregnant adolescents were younger. Ninety-four percent had used alcohol, 78% marijuana, 30% cocaine and 30% stimulants, compared with 92%, 48%, 14% and 23%, respectively, among women in the national sample. Among the pregnant adolescents, 84% had had more than one sexual partner, 39% had had a sexually transmitted disease and 60% had used contraceptives during less than half of their sexual encounters. At the bivariate level, use of cigarettes and alcohol in general and use of alcohol and drugs during sex were positively associated with risky sexual behavior. However, when other characteristics associated with risky sexual behavior--family bonding, parental monitoring, commitment to conventional values, peer associations, self-esteem and delinquent activities--were included in the multivariate analysis, the effect of substance use disappeared.