CHICAGO — Bisexual college women were 60% more likely to report having a sexually transmitted disease during the past year than were their heterosexual counterparts and four times more likely to report an STD than were lesbian college students, according to a study of 30,000 sexually active women.
“It's not clear whether it's the gender of their sex partners, the number of their sex partners, or the combination of these factors that increases their STD risk,” Lisa L. Lindley, Dr.P.H., said at a conference on STD prevention sponsored by the Centers for Disease Control and Prevention. “We need more research to understand the elevated sexual risk-taking of bisexual college women.”
Dr. Lindley, of the Arnold School of Public Health at the University of South Carolina in Columbia, drew her data from the spring 2006 National College Health Assessment, a survey of 117 postsecondary institutions, which included data on 95,000 male and female college students.
The majority of sexually active college women in the analysis were white (78%). Blacks and Hispanics constituted 10% of the sample, while students of other races and ethnicities rounded out the group. Most of the women (94%) were heterosexual; 1% described themselves as lesbians, 3% as bisexual, and 1% as unsure of their sexual orientation.
College women who reported having sex only with men during the past year had an average of two sex partners, as did those who reported having sex only with women. Women who reported sex partners of both genders during the past year had an average of five sex partners.
The college students also reported whether they had acquired an STD in the past year (HPV/genital warts, chlamydia, genital herpes, gonorrhea, and/or HIV). No significant differences were reported in the incidence of each STD based on students' sexual orientation, with the exception of HPV/genital warts. Lesbians were least likely to report having HPV/genital warts, while, compared with lesbians, heterosexual women had a fourfold increased risk, bisexual women had a sixfold increased risk, and those unsure of their sexual orientation had a fivefold increased risk.
When all the STDs were taken together, lesbian women had the lowest risk of infection—a 62% decreased risk, compared with heterosexual women. Bisexual women were 60% more likely to have an STD than heterosexual women were. But, compared with lesbian women with their very low rate, bisexual women were four times more likely to have an STD.
However, the study of also found that lesbian students were significantly less likely than either heterosexual or bisexual students to have had a routine gynecologic exam during the past year. While 73% of heterosexual women and 67% of bisexual women had an exam, only 46% of lesbian women did. “Therefore, it's likely that more lesbian women have an STD but don't know it,” Dr. Lindley said.
That finding prompts concern about the future sexual health of this group. “Educational efforts targeting lesbians must address the behavioral risk for STDs, safer sex practices, and the importance of regular gynecological exams and Pap tests,” said Dr. Lindley. “We also need additional research to understand why young lesbians do not seek these exams.”
Dr. Lindley also analyzed the incidence of multiple STDs by gender of sex partners. Women who had sex only with women during the past year had the lowest incidence of multiple infections (4%), while the incidence was 5% among those who had sex only with men. The incidence of multiple STDs was significantly higher in women who had partners of both genders (15%).
The analysis also pointed up an interesting dichotomy between the women's self-proclaimed sexual orientation and their actual sexual behaviors, Dr. Lindley noted. For example, 5% of women who self-identified as lesbians reported having only male sexual contacts in the past year, and 10% of lesbians reported having sex partners of both genders. Among bisexual women, 56% reported sexual contact with only men in the past year, and 10% reported sexual contact with only women; 35% of these women had sex with both men and women in the studied year.
Dr. Lindley reported that she had no financial disclosures.