Substance use among rural adolescent virgins as a predictor of sexual initiation

Longitudinal data from 746 virgins (310 males) aged 12 to 16 years were analyzed to assess the relationship between baseline substance use and sexual initiation 3, 6, and 9 months later. Compared to virgins with no substance use, virgins who had used three or more substances were three times more likely to initiate sex over the ensuing 9 months. The use of alcohol, tobacco, and marijuana and the use of more than three substances are highly specific for predicting sexual initiation.