PrEP sorting: HIV-negative gay men prefer sexual partners who are using PrEP

PrEP status is a significant factor for HIV-negative men who have sex with men (MSM) when selecting sexual partners, but not when choosing friends or romantic partners for dating, according to an American study published in AIDS Care. The authors investigated whether use of pre-exposure prophylaxis (PrEP) influenced partner selection on an online dating application. PrEP status was not a significant factor for HIV-positive men when it came to selecting sexual partners.

The authors suggest that ‘PrEP sorting’ – selection based on PrEP status – may work in the same manner as HIV serosorting works: men choose partners in a way they hope will reduce sexual infection risk. PrEP usage has had divisive effects, either being seen as a responsible preventative measure or an enabler of risky sexual behaviour amongst MSM. Some men using dating apps may be pro-PrEP and thus see the benefits in terms of reduced risk of HIV infection and PrEP users being regularly monitored for other STIs. Other men may be anti-PrEP, believing that men who use PrEP are promiscuous, engage in riskier behaviours with multiple partners and have more STIs.

The authors used vignettes in order to assess social attitudes of MSM on a popular geo-location sex app. Participants were presented with stories depicting gay male characters as either sexually promiscuous or monogamous and either taking PrEP or not. None of the characters used condoms. Participants were asked whether they would be friends, date, or have sex with the characters.



In HIV, refers to the act of telling another person that you have HIV. Many people find this term stigmatising as it suggests information which is normally kept secret. The terms ‘telling’ or ‘sharing’ are more neutral.


Choosing sexual partners of the same HIV status, or restricting condomless sex to partners of the same HIV status. As a risk reduction strategy, the drawback for HIV-negative people is that they can only be certain of their HIV status when they last took a test, whereas HIV-positive people can be confident they know their status

not significant

Usually means ‘not statistically significant’, meaning that the observed difference between two or more figures could have arisen by chance. 

adjusted odds ratio (AOR)

Comparing one group with another, expresses differences in the odds of something happening. An odds ratio above 1 means something is more likely to happen in the group of interest; an odds ratio below 1 means it is less likely to happen. Similar to ‘relative risk’. 


Studies aim to give information that will be applicable to a large group of people (e.g. adults with diagnosed HIV in the UK). Because it is impractical to conduct a study with such a large group, only a sub-group (a sample) takes part in a study. This isn’t a problem as long as the characteristics of the sample are similar to those of the wider group (e.g. in terms of age, gender, CD4 count and years since diagnosis).

A total of 339 men from nine US cities completed the full survey (18-81 years old, average age 37) in July 2015. Of these, 258 were HIV negative and not taking PrEP, 31 were HIV negative and taking PrEP, 25 were living with HIV and the other 25 did not know their status or declined to answer. Most of the men in the sample were white (52.5%) and single (68.7%), with a wide range of annual incomes.

Most participants (over 70%) in all three groups indicated that they would be friends with all the characters, regardless of PrEP use and promiscuity.

In terms of romantic dating, HIV-negative individuals not taking PrEP indicated that they preferred monogamous characters (OR = .02, 95% CI .01-.05, p <.0001) but PrEP use did not make a difference to preferences. PrEP users also rejected promiscuous men for dating, and appeared to prefer to date men on PrEP, but this difference was once again not significant. HIV-positive participants showed a preference for dating monogamous men using PrEP. While PrEP characters appeared to be preferred over those not taking PrEP (close to 80% said Yes to sex with monogamous PrEP users), this difference was not significant.

In terms of sex, HIV-negative participants not on PrEP preferred to have sex with men using PrEP (aOR = .18, 95% CI .09-.37, p < .0001). Participants taking PrEP preferred to have sex with those taking PrEP over those not taking it (aOR = 0, 95% CI 0-0, p < .0001). They largely rejected promiscuous characters not taking PrEP. While HIV-positive men preferred sex with monogamous PrEP characters, PrEP use was not significant in this instance.

These results indicate that HIV-negative MSM – either on PrEP or not taking it – desired PrEP users as sexual partners and thus shows evidence for sorting based on PrEP status. As this was a significant finding for HIV-negative but not for HIV-positive individuals in terms of sexual partner selection, it also is consistent with PrEP sorting being used as a risk mitigating strategy.

The authors caution that, as with HIV serosorting, a PrEP sorting strategy is only as effective as each individual’s knowledge of their most current status. A PrEP user (perhaps someone obtaining his medication informally) who does not test for HIV regularly and who has lapses in adherence may have a false sense of security about his HIV status.

An interesting finding was that the HIV-negative men not taking PrEP indicated that while PrEP usage was important for hook-ups, it was not important for dating. For HIV-positive individuals, while characters’ PrEP use did not have an effect on dating and sex in the statistical models, the most popular characters were monogamous and using PrEP. This may be because the combination of monogamy and PrEP use is seen as a more responsible way of having sex with HIV-negative individuals, and HIV-positive men may not feel as pressurised to disclose their status if they know their partner is on PrEP.

Another recent study published in AIDS and Behavior carried out with 104 MSM attending an STD clinic in Rhode Island revealed that amongst those who used online apps to meet other men (86%), 53% were more likely to contact a potential partner who disclosed being HIV negative, and 48% were more likely to do so if the person disclosed being on PrEP. This is further evidence for PrEP sorting while using online apps.

However, it does raise questions for HIV-positive men who openly disclose their status online, as 80% would be less likely to contact a man for sex if he disclosed being HIV positive and 57% would be less likely to contact an HIV-positive man who had an undetectable viral load. This highlights stigma and rejection of men living with HIV and that messages such as U=U (undetectable equals untransmittable) have not yet had a far-reaching effect.


Martinez, J.E. and Jonas, K.J. Pre-exposure prophylaxis sorting among men who have sex with men. AIDS Care, 2018.

Medina, M.M. et al. Disclosure of HIV Serostatus and Pre-exposure Prophylaxis Use on Internet Hookup Sites Among Men Who have Sex with Men. AIDS and Behavior, 2018, pp.1-8.