Assessing HIV risk among women who have sex with women: scientific and communication issues.

Data on human immunodeficiency virus (HIV) risk faced by women who have sex with women (WSW) are scarce. The biologic risk of female-to-female transmission is not known. Several surveys have reported that certain groups of WSW engage in behaviors that put them at risk for HIV infection, such as unprotected sex with men, unprotected sex or sharing of sex toys with women, and injection drug use. WSW may also be at risk for HIV through use of unscreened semen from sources other than sperm banks. An evaluation of HIV risk behaviors among WSW has been hampered by methodological issues, such as lack of data about the extent of the population, the use of standard definitions in research, and the design of data collection instruments. HIV prevention efforts have been hampered by communication issues, such as what "safer sex" means to this population and difficulties in interactions with health care providers. Prevention interventions for this population must address behaviors that put WSW at risk for HIV infection, including injection drug use and unprotected penile sex. At the same time, the possibility of sexual transmission of HIV via female-to-female sex should not be discounted. Health providers should understand that sexual identity does not necessarily predict sexual behavior and should not make any assumptions regarding HIV risk based on self-reported or presumed sexual identity.