The influence of peer norms on the process of early sexual initiation

Objective. To elucidate how different aspects of peer norms influence the process of sexual initiation for young adolescents. Design. A prospective cohort study. Setting. Fourteen elementary and middle schools in an urban public school district. Instrument. A 40 item pencil-and-paper survey of students\u27 demographic characteristics, self-reported risk behaviors, perceptions of peers\u27 behaviors, perceptions of peers\u27 norms and nominations for popular boys and girls. Participants. The 1,389 sixth-grade students who completed the questionnaire at the beginning (time 1) and at the end (time 2) of the school year comprises the study sample. Mean age at time 1 was 11.7 years. Results. Thirty-one percent of students (n = 442) reported having initiated sexual intercourse before sixth grade, 5% (n = 74) reported initiating sexual intercourse during the sixth grade school year (initiated group), and 64% (n = 873) reported not having initiated sexual intercourse by the end of the sixth-grade school year (never group). Logistic regression models for sexual initiation revealed that the strongest predictor of sexual initiation during the sixth grade is having high intention to do so at the beginning of the year. Belief that most friends have already had sexual intercourse is the strongest predictor of high intention. Popular nominations were tallied for all students. Those receiving more than one standard deviation above the mean number of nominations in their school at both time points were identified as popular students (n = 132, 9% of sample). Rates of sexual intercourse were dramatically higher for popular students compared to their peers (47.0% vs. 16.8%, p \u3c 0.001) at the beginning of the sixth grade. Popular students were more likely than their peers to initiate use of cigarettes (24.4% vs. 18.7%, p = 0.02) and alcohol (21.4% vs. 16.9%, p = 0.007) during the sixth grade. While nomination of a high-risk popular boy influenced boys\u27 initiation of cigarette smoking (p = 0.02), alcohol use (p = 0.15) and sexual intercourse (p = 0.01), affiliation with a high-risk popular girl did not significantly influence girls\u27 initiation of these three behaviors. Conclusions. Early sexual initiation is not an unplanned experience for many young adolescents. Decisions about initiation are strongly bound to social context with popular students playing a particularly important role