Programmes that exclusively encourage abstinence from sex do not seem to affect the risk of HIV infection in high income countries, finds a review of the evidence in this week's British Medical Journal.
This also calls into question the continued use of public money to fund abstinence only programmes in the United States.
Abstinence only programmes encourage sexual abstinence as the exclusive means of preventing HIV infection, without promoting safer sex behaviours, but their effectiveness in high income settings remains unclear.
At present, thirty-three per cent of HIV prevention funds from the US President's Emergency Plan for AIDS Relief (PEPFAR) are used for abstinence only programmes. This limits the funding available for other safer sex strategies. Domestic US programs also receive substantial federal and state funding.
A pre-existing review has already examined programme effectiveness in low income countries, so researchers at the University of Oxford reviewed 13 trials involving over 15,000 US youths to assess the effects of abstinence only programmes in high income countries.
Programmes aimed to prevent HIV infection or HIV and pregnancy. They measured self reported biological and behavioural outcomes such as sexually transmitted infection, pregnancy, frequency of unprotected sex, number of partners, and sexual initiation.
Compared with various controls, no programme had a beneficial effect on incidence of unprotected vaginal sex, number of partners, condom use, sexual initiation, incidence of pregnancy, or incidence of sexually transmitted infection.
The results also suggest that abstinence only programmes did not increase primary abstinence (prevention) or secondary abstinence (decreased incidence and frequency of recent sex).
Despite some study limitations, these conclusions are consistent with previous reviews that found no evidence of an effect of abstinence only programmes in developing countries or the United States, say the authors. They call for more rigorous evaluations of these programmes in the future.