Although the vast majority of teenagers in a clinic-based study in Singapore knew that AIDS is incurable, this knowledge was not a predictor of sexual initiation; however, those who had read or seen media portrayals of individuals with HIV, AIDS or other STDs were considerably less likely to be sexually experienced than were those who had not.1 Among males, the strongest predictor of sexual initiation during adolescence was exposure to pornographic materials, which also was positively—although more moderately—associated with sexual experience among females. For females, the strongest predictor of sexual initiation was a history of sexual abuse.
The study, conducted in 2006–2008, compared a sample of never-married 14–19-year-olds visiting Singapore’s only public STD clinic with a sample of sexually inexperienced youths attending a primary care clinic; members of the control group were matched to STD clinic clients according to age, gender and ethnicity. STD clinic clients were eligible to participate only if they reported that their most recent sexual encounter (vaginal, oral or anal intercourse) had been voluntary. In all, 500 teenagers from each clinic—264 males and 236 females—were included in the study. Participants completed a face-to-face interview, along with a self-administered questionnaire (on sensitive topics), to provide information on their background characteristics, sexual behavior and related attitudes, and exposure to sexual content in the media.
Univariate analyses revealed a number of differences between sexually experienced and inexperienced adolescents. The former were more likely than the latter to report characteristics suggesting socioeconomic disadvantage and to say that they had engaged in a variety of risk behaviors. The two groups were equally unlikely to think that AIDS is curable (6–7% of males and 6% of females in each group gave this response) and to believe that it is possible to tell that a person has HIV or AIDS just from appearances (19–24% of males and 15–19% of females). However, sexually experienced teenagers reported a more liberal attitude toward premarital sex and less confidence in their ability to resist peer pressure to have sex. Questions about parental relationships, peer characteristics and the school environment generally yielded similar responses from the two groups; a notable exception was that a greater proportion of sexually experienced participants than of controls believed that at least half of their peers had already had sex (46% vs. 13% among males and 52% vs. 14% among females).
Measures of exposure to media with sexual content also were largely similar in the two groups. However, sexually experienced adolescents were more likely than controls to report ever having read or watched pornography (95% vs. 79% among males and 73% vs. 37% among females); males with sexual experience also were less likely than others to say that they had read about people with STDs or had seen TV shows, movies or videos including such individuals (16% vs. 46%). Finally, sexually experienced females were more likely than controls to have a history of sexual abuse (23% vs. 3%) and gave their parents lower scores on an index measuring authoritativeness.
In separate analyses for female and male respondents, the researchers used bivariate logistic regression to identify potential predictors of adolescent sexual experience. Most of the characteristics examined were significant in these calculations and were entered into multivariate models. Exceptions included knowledge about AIDS (e.g., that it is not curable) and degree of exposure to media with sexual content.
The strongest predictor of teenage sexual initiation emerging from the multivariate analysis for males was exposure to pornography: The odds of sexual experience were almost six times as high among male participants who had ever read or watched pornographic material as among those who had not (odds ratio, 5.8). Males’ likelihood of being sexually experienced also was positively associated with drinking and smoking (1.8–1.9), and with living in low-cost housing, reporting involvement in gang activities, approving of premarital sex, perceiving that a majority of their friends had had sex and lacking confidence in their ability to resist peer pressure to have sex (3.3–3.8); it was negatively associated having seen or read media portrayals of individuals with STDs (0.3).
Among females, having a history of sexual abuse was the strongest predictor of sexual experience: Participants reporting such a history had markedly higher odds than others of having initiated sex (odds ratio, 7.8). The likelihood of being sexually experienced also was elevated among females who had dropped out of school, used alcohol, did not consider their mother a confidante, thought that the majority of their friends were sexually experienced or had ever read or watched pornography (2.1–3.2); lived in low-cost housing or did not feel that they could resist peer pressure to have sex (4.5–5.6); or had a liberal attitude toward premarital sex (6.3). Like their male counterparts, females who had read or seen media portrayals of people with STDs had reduced odds of having had sex (0.2).
The researchers observe that the clinic-based setting of their study limits the generalizability of its findings, and that biases inherent in self-reported data may have affected the results. Nonetheless, they believe that several of their findings may have implications for teenagers’ healthy sexual development. They note that adolescents’ feeling that they cannot resist peer pressure to have sex, a risk factor for both females and males in this sample, is potentially modifiable and should be a target of education interventions. Further, given that sexual initiation was not related to participants’ knowledge about AIDS but was negatively associated with exposure to media portrayals of individuals with STDs, the researchers recommend that TV shows be used as a vehicle for information about STDs and life skills education. Finally, they suggest that "the strong association of pornography with adolescent sexual initiation" calls for steps "to monitor, to reduce, or to restrict access to explicit sexual media and pornography for adolescents."—D. Hollander
1. Wong M-L et al., Premarital sexual intercourse among adolescents in an Asian country: multilevel ecological factors, Pediatrics, 2009, 124:e44–e52, <http://www.pediatrics.org/cgi/content/full/124/1/e44>, accessed July 8, 2009.