NEW YORK (Reuters Health) ¿ In high income countries, programs that encourage abstinence from sex as the only method of preventing HIV infection are not effective in achieving this goal, findings from a review of trial data suggest. As reported in this week's issue of the British Medical Journal, Dr. Kristen Underhill and colleagues, from the University of Oxford in the UK, searched 30 electronic databases to identify studies that examined the effectiveness of abstinence-only programmes as a means of preventing HIV infection.

Data from 13 trials, containing nearly 16,000 US youth, were included in their analysis. Compared with no programme, safer sex programs, and various other control programmes, the abstinence-only programmes did not seem to reduce HIV risk. Specifically, abstinence-only programmes did not influence the rate of unprotected vaginal sex, the number of sexual partners, condom use, or initiation of sexual activity. In one trial, there was evidence that abstinence-only programmes may have had an adverse effect. Compared with a comparison group of young people who did not participate in an HIV prevention programme, abstinence-only programmes were associated with a rise in sexually transmitted infections and pregnancy. Still, the authors note that other trials did not show a significant link between abstinence-only programmes and these outcomes.

In another trial, there was a suggestion that abstinence-only programmes may reduce levels of vaginal sex, but the follow-up period was relatively short.

"In contrast to abstinence only programs, programmes that promote the use of condoms greatly reduce the risk of acquiring HIV, especially when such programmes are culturally tailored behavioral interventions targeting people at highest risk of HIV infection," Dr. Stephen E. Hawes, from the University of Washington in Seattle, wrote.