Explicit Relationship Agreements and HIV Pre-exposure Prophylaxis Use by Gay and Bisexual Men in Relationships.

Relationship agreements are important for HIV prevention among gay and bisexual men (GBM) in relationships, with research earlier in the HIV epidemic often finding that agreements specified monogamy or condom use with casual partners. There is evidence that HIV pre-exposure prophylaxis (PrEP) has shifted sexual practices among some men in relationships, such as allowing condomless sex with casual partners, but there has been little attention paid to relationship agreements among GBM who use PrEP. In this paper, we analyzed national, Australian, cross-sectional data from an online survey completed by non-HIV-positive GBM in 2021 (N = 1,185). Using logistic regression, we identified demographic characteristics, sexual practices and the types of relationship agreement that were associated with PrEP use among GBM in relationships. Using Pearson's chi-squared tests, we explored whether PrEP users in relationships reported similar sexual practices to PrEP users not in relationships. PrEP use among GBM in relationships was independently associated with older age, identifying as gay, being in a non-monogamous relationship, having a spoken (explicit) relationship agreement, having a primary HIV-negative partner taking PrEP or a primary partner living with HIV, reporting recent condomless casual sex, reporting an STI diagnosis in the past year, and knowing at least one other PrEP user. We found that PrEP users in relationships had similar sexual practices to PrEP users not in relationships. GBM in relationships who have casual sex and who meet PrEP suitability criteria may be good candidates for PrEP. Our findings suggest that explicit relationship agreements remain important for HIV prevention, and they support PrEP use among GBM in relationships.