Roughly three-quarters of lesbians who responded to a magazine survey have had sexual intercourse with men, and nearly two-thirds have had unprotected heterosexual intercourse. One-sixth of respondents have ever had anal intercourse with a male partner, and the same proportion have ever had a sexually transmitted disease (STD). Researchers analyzing the survey results point out that clinicians should be aware of the need to take a full sexual history of their lesbian patients, so opportunities to refer women for needed Pap smears or STD screening will not be missed.1
The data come from responses to a 186-item questionnaire that was included as an insert in the March 1995 issue of The Advocate, a national newsmagazine for gay, lesbian and bisexual men and women. The sample of 6,935 self-identified lesbians who returned the questionnaire responded to items asking about their sexual experience with men and about their history of STD testing and diagnosis. Respondents were also asked to provide information on their social and demographic characteristics, including race or ethnicity, age, annual income, educational attainment and population size of their community. Researchers performed multivariate logistic regression analyses (with the variables that proved significant in bivariate analyses) to determine which factors independently affected women's likelihood of ever having had vaginal intercourse, of having had sexual intercourse without a condom and of having had a male sexual partner in the previous year.
The majority of the women were white (88%), were aged 25-49 (85%) and had graduated from college (63%). Seventy percent reported an annual income of more than $20,000, and 35% lived in cities of more than a million people.
Six percent of the sample had had sex with a male partner in the past year. Some 77% had ever had a male sexual partner, and 71% had had penile-vaginal intercourse; while the first of these proportions varied significantly by the respondent's race, age, education and community size, the latter varied significantly by all five characteristics under study. The proportion ever having had intercourse without a condom--64%--also varied significantly by each characteristic, except for community size. One-sixth of the women (17%) had ever had anal intercourse, and a similar proportion (16%) had ever done so without a condom; the proportion ever having had anal intercourse differed significantly by the respondent's age, education and community size, and the proportion ever having had unprotected anal intercourse varied by these same three characteristics, plus income.
Overall, 17% of the sample had had an STD; this proportion was significantly higher among lesbians who had ever had heterosexual intercourse than among those who had not (21% vs. 7%). Similarly, the proportion testing positive for an STD was significantly greater among those who had had anal intercourse (31%) than among those without such experience (14%).
While the overall proportion who had ever had an abnormal Pap smear was 17%, it rose to 20% among lesbians who had ever had penile-vaginal intercourse and to 26% among those who had ever had anal intercourse. Again, the proportions were significantly lower among lesbians who had not participated in these activities (10% and 16%, respectively).
Rates of HIV testing were higher in the subgroups of lesbians who had experienced anal (63%) or vaginal (58%) intercourse than in the overall sample (53%). Nevertheless, among those who had engaged in unprotected anal or vaginal sex, two-fifths had never had an HIV test.
In the multivariate analyses, the variables that independently raised lesbians' likelihood of having had a male sexual partner within the past year were young age, low income, nonwhite race and not having graduated from college. For example, respondents younger than 25 were 6.7 times as likely as those older than 50 to have had a male partner in the past year; lesbians with an annual income of less than $20,000 were 1.5 times as likely as those who made more than $50,000 to have done so; nonwhites were 1.4 times as likely as whites to have had a recent male partner; and non-college graduates were also 1.4 times as likely as graduates of a professional school to have had a male sexual partner in the past year.
Advocate readers who had not graduated from college were significantly more likely than those with a postgraduate degree to have ever had heterosexual intercourse (odds ratio, 1.5). Lesbians younger than 50 were significantly less likely than older women to have done so (0.4-0.7); respondents who lived in either rural areas or in cities of fewer than one million inhabitants also had a reduced likelihood of having had heterosexual sex (0.8).
Among respondents with a history of vaginal intercourse, women younger than 25 were substantially less likely than those older than 50 to have ever had heterosexual intercourse without a condom (odds ratio, 0.2); those aged 25-50 also had reduced odds of having had unprotected vaginal intercourse (0.5). Respondents who had not graduated from college had slightly elevated odds of having had penile-vaginal intercourse without a condom (1.6). This analysis also took into account the number of male partners a woman had had, and the results are dramatic. Compared with respondents who had had sex with only one man, those who had had 2-5 male partners were 2.3 times as likely, and those who had had six or more male partners were 11.2 times as likely, to have had unprotected penile-vaginal sex.
The researchers affirm that because the study did not use probability sampling, its generalizability to all U.S. lesbians is limited. What is more, they acknowledge that respondents to sex surveys tend to hold more liberal sexual attitudes and be more sexually active than those who choose not to respond; this sample of magazine readers was also relatively affluent and well educated. According to the researchers, however, the magazine-insert approach improved on previous efforts to ascertain levels of sexual activity among U.S. lesbians, since it was a broad-based media solicitation that reached a large number of lesbians in all 50 states.
The data reveal that substantial proportions of lesbians have engaged in sexual activity with men, which places them at risk for a range of STDs and for cervical cancer. Therefore, the researchers assert that if clinicians automatically assume that lesbians have had no sexual contact with men, these health professionals might miss opportunities to give appropriate advice or recommendations to patients in their care. They conclude that "it is important for the clinician to know a patient's complete medical and social history, including current and past sexual activity, to make appropriate decisions regarding the provision of appropriate health care."--L. Remez
REFERENCE
1. Diamant AL et al., Lesbians' sexual history with men: implications for taking a sexual history, Archives of Internal Medicine, 1999, 159(22):2730-2736.