The risks of transmission of STDs and HIV from heterosexual intercourse are clear, however, there is less information available about the risks of transmission from woman to woman. Women who only have sex with women can transmit STDs via skin contact, the sharing of vaginal secretions from hands and from shared sex toys, and via oral-genital or oral-anal contact. Many lesbian women, however, have had sex with men in the past and may continue to have sex with men despite a self-identification as a lesbian. In one study of over 1200 lesbians and bisexual women, 85% report past or present sexual activity with men and 98% report past or present sexual activity with women.
The incidence of syphilis, gonorrhea and chlamydia among women who only have sex with women is rare  . Rates of herpes, HPV and HIV infection are also lower among women who have sex with women only.
Genital infection with bacterial vaginosis and candidal vulvovaginitis is more frequent in women who have sex with women and several studies have shown a higher prevalence of bacterial vaginosis in lesbian women than in heterosexual women . Recurrent vaginal infections are also an indication for HIV testing.
There is a perception in both the lesbian community and in the medical community that there is little or no risk of HIV transmission during sex between women . In addition, lesbian women have been largely ignored and left out of HIV prevention and education strategies. This results in lesbian women believing their risk of contracting HIV to be low. However, there are case reports of female-to-female HIV transmission    . Globally, women are the group most at risk for HIV infection and, even in the United States, an increasing proportion of new HIV cases are among women. HIV rates are low among lesbian women, but there are groups at high risk such as injection drug users, crack cocaine users, women who have unprotected sex with high-risk men and commercial sex workers. Bisexual women are also more likely than heterosexual women to engage in HIV risk behaviours such as injection drug use, and unprotected vaginal and anal intercourse  12,13.
13. Anonymous [Council on Scientific Affairs, American Medical Association]. Health care needs of gay men and lesbians in the United States. Journal of the American Medical Association. 1996;275(17):1354-1359.
15. Hudspith M. Caring for Lesbian Health: A Resource for Canadian Health Care Providers, Policy Makers and Planners, Revised Edition. 2001. Health Canada. http://www.hc-sc.gc.ca/english/women/facts_issues/lesbian_health.htm. Accessed October 24, 2003.