A Safe Age for Sex? Sexual Debut Timing in Adolescence and Consequences for Adult Health

Intro

For over 75% of American youth today, sexual debut occurs in the teenage years. Yet despite its ubiquity – and possible developmental appropriateness for some in the later teens– adolescent sexual behavior is still seen as risky. Research suggests that early sexual initiation is associated with increased risk for negative sexual health outcomes, such as STI contraction and early pregnancy. Most studies set a cutoff age for early initiation based on either national averages or sample characteristics. We are aware of only one study that has examined consequences of sexual initiation across different ages in adolescence. There is also evidence that links early sexual onset to depression in young adulthood. However, the extent to which other health consequences later in adulthood are related to timing of initiation is unclear. Further, whether the relationship between early sexual initiation and adult health problems is due to the confounding with proximal sexual consequences is unknown.

Method

Data came from the Seattle Social Development Project (SSDP), a longitudinal study that began in 1985. The sample is gender-balanced (n=808, 49% female) and ethnically diverse (47% European-American, 26% African-American, 22% Asian-American, and 5% Native American). Age of sexual initiation, early pregnancy, and STI status by age 21 were based on prospective and retrospective self-reports. Negative adult health outcomes were measured at ages 30-39 and include alcohol disorder, nicotine disorder, marijuana disorder, depression, poor health, and obesity. Data were analyzed using time-varying effect modeling (TVEM), a method based on spline regression, which estimated the probability of each of the adult health problems at each year of sexual initiation from 10 to 21.

Results

Overall, results showed that earlier sexual initiation is associated with an increased probability of each of the adult health outcomes except depression. Initiation before 13 was particularly risky and initiation after 18 conferred less risk. Findings suggest that accounting for proximal negative sexual outcomes decreased the relationship between negative adult health outcomes in the 30s and age of initiation. This was particularly true for the middle adolescent years.

Implications

There is a need for empirically based guidelines for a safe age of adolescent sexual initiation and a better understanding of the long-term risks. It is particularly critical to understand the risks of poor adult health for the adolescents who initiate sex in middle adolescence, as these years see the highest rates of sexual debut. If, after accounting for proximal sexual consequences, the risks are few, prevention should focus on reducing the likelihood of such consequences rather than increasing age of initiation.