Individual, familial, friends-related and contextual predictors of early sexual intercourse.

This study examined the unique and simultaneous contribution of adolescents' characteristics, parent-child relationship and friends' characteristics on early sexual intercourse, while accounting for family status. A longitudinal multi-sample design was used. The first sample was recruited in a suburban context (n = 265; 62% girls) and the second sample in an urban setting (n = 136; 61% girls). All predictors were measured in Grade 8 and age at first intercourse was assessed yearly for three years. Being in a non-intact family, low parental control, high antisocial behaviors, low self-disclosure, high proportion of other-sex friends and high substance use were associated with earlier sexual intercourse. When all predictors were considered simultaneously, more antisocial behaviors, high proportion of other-sex friends and non-intact family structure significantly discriminated youth reporting first intercourse at age 13 or less from those who reported first intercourse at age 14, at age 15, or were virgins at age 16 among both samples.