A prospective study of intraindividual and peer influences on adolescents' heterosexual romantic and sexual behavior.

Theories and empirical studies of adolescent sexual behavior have identified the contributions of personal attributes and social experiences; however, it is rare that models have clarified developmental pathways to adolescent sexual behavior that include (1) factors assessed prior to and early in adolescence and (2) dyadic experiences in adolescence that provide the opportunity for sexual behavior (i.e., dating). Using data from a prospective study, structural equation modeling was used to test a model predicting adolescent sexual behavior at age 19, denoted by the number of lifetime sexual partners. Predictors examined were sociability and impulsivity assessed at 30 months of age, physical characteristics and experiences with peers measured at age 12-13, the age of first romantic relationship, and frequency of alcohol use at age 16. The pathway to greater sexual involvement was marked by some desired personal attributes (e.g., sociability) and peer experiences (e.g., higher quality friendships). These associations were mediated, however, by earlier initiation of romantic relationships and more frequent use of alcohol in middle adolescence. Earlier initiation of romantic relationships and more frequent alcohol use were predicted by greater sociability and less impulsivity in childhood, higher quality friendships and greater peer acceptance in early adolescence, and a more mature appearance and physical attractiveness (among females) at age 13. The findings imply a complex pathway that leads to a greater accumulation of sexual partners by age 19. This pathway begins in childhood and includes individual qualities, peer acceptance, romantic relationships, and alcohol use.