NEW YORK More than 10% of teens in New York City public high schools who have ever had intercourse reported bisexual behavior in a 2005 survey, according to a recent analysis.
Those teenagers reported a higher prevalence of risky sexual behaviors, including lower rates of condom use and a greater number of sex partners, researchers from the New York City Department of Health and Mental Hygiene and the Centers for Disease Control and Prevention found.
The analysis is based on responses to the New York City Youth Risk Behavior Survey, a population-based survey of in-school adolescents.
Of 1,881 males who reported ever having had intercourse, 94% reported opposite sex partners, 3% reported same-sex partners, and 3% reported partners of both sexes. Of 1,705 females who reported ever having had intercourse, 88% reported opposite sex partners, 3% reported same-sex partners, and 9% reported partners of both sexes.
Males and females were equally likely to report same-sex only behavior, but females were more than three times as likely to report bisexual behavior, Preeti Pathela, Dr. P.H., a research scientist at the New York City Department of Health and Mental Hygiene, said at a joint conference of the American Sexually Transmitted Diseases Association and the British Association for Sexual Health and HIV.
Of males who reported both male and female sex partners, they reported an earlier age of sexual debut, compared with the heterosexual and homosexual respondents.
Males who reported partners of both sexes also were more likely than the other two groups to report a greater number of lifetime and recent sex partners.
For the males who reported sex in the previous 3 months, 83% of those with partners of both sexes reported sex with two or more partners, compared with 46% of those who had opposite-sex partners and 28% of those with same-sex partners.
About 28% of the males with partners of both sexes reported condom use at last sex, compared with 77% of homosexual males and 79% of heterosexual males.
Among females, the patterns were somewhat different, Dr. Pathela said.
Females with partners of both sexes and those with same-sex partners only were both more likely than those with opposite sex partners only to report a greater number of lifetime and recent sex partners. Females who had partners of both sexes were also more likely than those with opposite sex partners only to report alcohol and drug use at last sex, she said.
The researchers also found that in many cases the sexual identity given by the respondents and the behaviors they reported did not match up. For example, they found the greatest discordance in males who had same-sex partners only but reported a heterosexual identity.
Discordant findings were even more striking in females, Dr. Pathela said. Among those who reported having only female partners, 79% of girls identified as heterosexual but engaged in same-sex behaviors only and 13% whose sexual identity was bisexual engaged only in same-sex behaviors. And in females with partners of both sexes, 26% considered themselves heterosexual.
Given the discordance between teens' sexual behavior and sexual identity, physicians need to inquire about sexual behaviors, not just identity, to assess risk, Dr. Pathela said.
The findings also have implications for prevention campaigns, she said. These messages must be appropriate for a broad audience of teens with same and opposite sex partners, she said.
Sexual health education should also include advising youth to inquire about the sex of their partners' partners, Dr. Pathela advised.