Heterosexual vaginal and anal intercourse amongst London heroin and cocaine users.

A community-derived sample of 392 heroin users and 145 cocaine users were interviewed about their drug use and sexual behaviour, with (optional) collection of saliva specimen for linked anonymous HIV/HBV testing. The heroin sample was stratified (50/50) across current treatment and non-treatment status. For cocaine users 80% were not in current contact with any treatment. Overall levels of sexual activity were several times higher than reported in recent national surveys. Last-year prevalence of heterosexual anal intercourse was 23% and 20% for heroin-using males and females respectively (last-month figures--12% and 10%); and 23% and 15% for cocaine-using males and females respectively (last-month figures--7% and 9%). Two-thirds of subjects rarely or never used condoms during heterosexual anal intercourse. For females, receptive anal intercourse was positively related to a history of sex-for-money activity, high scores of severity of dependence, and injecting as a current route of use.