Presenting Author:

Julia Napolitano, Research staff

Principal Investigator:

Brian Mustanski



condom, HIV risk, PrEP, gender, sex, anal sex, partner, relationship


Third Floor, Feinberg Pavilion, Northwestern Memorial Hospital

PH46 - Public Health & Social Sciences

Partner Gender & PrEP effects on Condomless Sex among YMSM

AIMS: Previous studies have explored the relationship between individual-level HIV risk behaviors (e.g. condomless sex) and protective factors (e.g. PrEP). However, few studies investigate partner characteristics as predictors of an individual’s risk and protective behaviors. In this poster, we ask whether partner gender identity, partner-reported PrEP use, and relationship status predict the frequency of condomless anal sex acts. We further examine the relationship between partner gender identity and sexual positioning, which has implications in HIV risk reduction conversations. SAMPLE: Data were collected from an ongoing longitudinal cohort study of YMSM in Chicago. Participants were between 16-29 years of age, assigned male at birth, spoke English, and had a sexual encounter with a man in the previous year or identified as gay, bisexual, or transgender. Participants completed a sexual health questionnaire every six-months, reporting the number of different sexual behaviors with up to four of their most recent sexual partners. METHODS: Linear regression models were utilized to predict the number of insertive and receptive condomless anal sex acts based on partner gender, participant PrEP use, and partner PrEP use. Relationship type, partner HIV status, partner race, age difference, and whether the partner had been reported at a previous visit were included as covariates. These were partner-by-partner analyses that controlled for within-subjects variance and included only HIV negative participants. RESULTS: Overall, 6079 (92%) of sexual partnerships involved cisgender male partners, versus 112 (1.7%) with transgender or gender non-conforming (TGNC) male and 374 (5.67%) cisgender females. Participants with TGNC partners reported a higher frequency of condomless insertive anal sex (β=1.34, p<.005) compared to cisgender male partners. If a participant reported a TGNC partner, frequency of condomless receptive anal intercourse (CRAI) was lower (β=-2.05, p<.0001). If participant reports partner is on PrEP, frequency of CRAI increases (β=.633, p<.01) but participants own PrEP use is not significantly related to frequency of CRAI (p=.775). In terms of partnership variables, being in a serious relationship and having a repeat partner are associated with a higher frequency of CRAI (p<.001 and p<.004). DISCUSSION: These results show that partner gender affects the frequency of condomless sex acts, as does relationship status. Additionally, for receptive anal sex, a partner’s reported PrEP use is a predictor of CRAI whereas one’s reported use of PrEP is not. This raises concerns about whether reporting on partner-level PrEP use is reliable and how receptive partners may make decisions about PrEP based on partner rather than their own health. Integrating a more nuanced understanding of partner characteristics’ effect on sexual behavior in YMSM could inform a stronger approach to PrEP marketing and discussions of HIV risk reduction in clinical settings.