Exploring preferences for long-acting injectable PrEP among postpartum women in South Africa using the consolidated framework for implementation research: the Siphila Sonke study

South African women are disproportionately affected by HIV, with increased incidence during pregnancy and postpartum. While oral TDF/FTC pre-exposure prophylaxis (PrEP) is safe, effective, and recommended for pregnant and postpartum women, adherence to a daily pill is challenging, particularly during the postpartum period. Longer-acting injectable (LAI) PrEP products may be more desirable for postpartum women however, limited data on factors influencing uptake are available to inform roll-out of LAI products among postpartum women. Using the Consolidated Framework for Implementation Research (CFIR), we explored LAI PrEP implementation determinants among postpartum women in South Africa. From March-April 2023, 4 focus group discussions (FGDs) were conducted among postpartum women in KwaZulu-Natal. A directed content analysis method was performed. Among 23 women, median age was 27 (range 19–36) years. Two (9%) reported a pregnancy partner living with HIV, 7 (30%) had ever used PrEP, and 21 (91%) had ever breastfed. Factors that may influence LAI PrEP implementation are organized by three CFIR domains. Individuals expressed interest in and potential willingness to use LAI PrEP, but limited knowledge. At the implementation process domain, participants perceived LAI-PrEP users to have high HIV risk perception, and were themselves worried about side-effects, access, and fear of partner conflict. They also identified implementation opportunities including peer PrEP mentors, mobile clinics, and community clinic integration. At the outer setting, cultural beliefs/practices during postpartum were important determinants. Our findings indicate interest and willingness to consider LAI PrEP among postpartum women and highlight implementation opportunities to reduce HIV acquisition and perinatal transmission.