Enablers and barriers to oral HIV pre-exposure prophylaxis (PrEP) adherence among female sex workers in Southeast Oromia, Ethiopia: a mixed-method study

Pre-Exposure Prophylaxis (PrEP) is a key HIV prevention strategy, yet low adherence remains an issue, particularly among female sex workers (FSWs). This study aims to assess the level of adherence to oral HIV pre-exposure prophylaxis and its enablers and barriers among FSWs in Southeast Oromia, Ethiopia. A facility-based cross-sectional mixed-methods study was conducted from June 1 to August 31, 2024. For the quantitative component, 348 FSWs on PrEP follow-up were selected using simple random sampling. Data were entered in Epi Info 7.2.1 and analyzed using SPSS 26. Bivariable and multivariable binary logistic regression analyses were performed to identify factors associated with PrEP adherence, with associations measured using odds ratios (ORs) and 95% confidence intervals. Statistical significance was declared at p < 0.05. The qualitative component involved in-depth interviews with 11 FSWs, and the data were analyzed thematically based on the socio-ecological framework using qualitative data analysis (QDA) Miner Lite version 4.0. The proportion of FSWs who had good adherence to PrEP was 61.1% (95% CI = 55.8–66.5). In the final model, younger age (18–23 years: AOR = 0.29, 95% CI: 0.11–0.77; 24–30 years: AOR: 0.19, 95% CI: 0.07–0.51), concerns about PrEP effectiveness (AOR: 0.28, 95% CI: 0.15–0.55) and side effects (AOR: 0.44, 95% CI: 0.23–0.83), being on PrEP < 3 months (AOR: 0.36, 95% CI: 0.16–0.84), and experiencing side effects (AOR: 0.09, 95% CI: 0.04–0.21) were negatively associated with adherence, while self-perceived high (AOR: 3.17, 95% CI: 1.43–7.02) and medium HIV risk (AOR: 2.34, 95% CI: 1.12–4.88) and using phone alarms as reminders (AOR: 3.16, 95% CI: 1.29–7.72) were positively associated. Qualitative findings indicated that disclosure to trusted friends, KP-friendly facility incentives, and adherence counseling enabled PrEP use, while PrEP packaging, alcohol use, fear of stigma, and living with peers were barriers to adherence among FSWs. A substantial proportion of FSWs were non-adherent to PrEP. Key barriers included concerns about effectiveness and side effects, short PrEP experience, packaging, daily dosing, alcohol use, stigma, and living with peers, while facilitators were high self-perceived HIV risk, phone alarms, disclosure, incentives, and adherence counseling. Addressing these barriers could improve adherence and strengthen HIV prevention efforts among FSWs, supporting broader epidemic control.