Linkages between sexual activity and alcohol and drug use among American adolescents.

Among a nationally representative cohort of young men and women reaching maturity in the late 1970s and early 1980s, over three-fourths of males and half of females had sexual intercourse by age 19, and a substantial minority used marijuana prior to their 16th birthday. However, in most cases, much smaller proportions began weekly alcohol consumption, tried drugs besides marijuana or experienced sexual intercourse before age 16. Males are generally more likely to have begun participating in these activities, at all ages, than are females. Only modest percentages of youths participated in more than one activity at early ages or engaged in them in close proximity to one another. Indeed, only by age 19 did even one-third of the young women engage in sexual intercourse and use both marijuana and alcohol. In fact, the norm for girls under 17 and for boys under 16 is either abstention or participation in just one activity. Although younger blacks are more likely to have initiated sexual activity than are their white or Hispanic counterparts, young minority women are less likely than white women to have begun using alcohol or marijuana. Young people who use one or more substances by a given age are more likely than those who do not to become sexually active within a year. However, marijuana use at a young age appears to be more strongly linked to subsequent sexual initiation than is regular monthly alcohol use.(ABSTRACT TRUNCATED AT 250 WORDS)