The results of three annual surveys show that the decisions faced by gay men are much more complex than the decision whether or not to use a condom.
Choices range in terms of the likely degree of protection from HIV they offer: from avoiding sex or anal sex altogether to at least avoiding unprotected anal sex with someone known to have the opposite HIV status.
Using condoms 100% of the time for anal sex is still the most popular single strategy, the study found, but only a third of HIV-negative men and a quarter of HIV-positive men now do this.
Taken as a whole, strategies involving basing whether to have unprotected anal sex on a partner's HIV status (serosorting) are now at least as popular as consistent condom use.
The study found a clear difference between serosorting practices according to participants' HIV status. The second most popular safer-sex strategy for HIV-negative men was to restrict unprotected sex to an HIV-negative regular partner – a strategy that has been called 'negotiated safety'.
HIV-positive men were less likely to restrict unprotected sex solely to their primary partner; instead the most popular strategies were to limit unprotected anal sex, both with regular and casual partners, to other HIV-positive partners – or at least to try and exclude having it with regular and casual partners not known to be HIV positive.