Outcomes of Early Adolescent Sexual Behavior in Australia: Longitudinal Findings in Young Adulthood

Purpose: Limited longitudinal research has examined the adult health and behavioral outcomes associated with early adolescent sexual behavior. This paper examined whether adolescent sexual behavior predicted young adult health and social outcomes within longitudinal cohorts in Victoria, Australia. Methods: Adolescents were recruited in 2002 to be state-representative of school students in Victoria, Australia, and resurveyed in 2003 and 2004. The sample responded to a web-based survey as young adults in 2010/2011. Multivariate negative binomial regression models examined the predictive effect of sex by age 15 on young adult outcomes (average age 21) of sexual risk taking, substance use, antisocial behavior, and psychological distress (N = 2,147). Results: After adjustment for other factors, sex at age 15 or younger (early sex) predicted higher rates of young adult sexual risk taking such as pregnancy, lifetime partners, and sex without using a condom. Early sex also predicted higher rates of young adult substance use (alcohol, tobacco, and/or illicit substance use) and antisocial behavior, but rates of adult psychological distress were not affected. Conclusions: This study found that early adolescent sex had unique predictive effects on a range of adverse young adulthood outcomes. Public health policies should synthesize longitudinal data on the risks of early sexual behavior, while advocating evidence-based adolescent sexual health promotion interventions.