Patterns of HIV Pre-exposure Prophylaxis use Among Adolescent Girls and Young Women Accessing Routine Sexual and Reproductive Health services in South Africa.

Purpose: This study describes the patterns of pre-exposure prophylaxis (PrEP) use among adolescent girls and young women (AGYW) initiated on daily oral PrEP for the prevention of HIV, within routine sexual and reproductive health services in South Africa.

Methods: We analysed clinical and survey data from a nested cohort of 967 AGYW initiated on oral PrEP between January 2019 and December 2021 in four geographical clusters in South Africa. We describe the periods of PrEP use, and the proportion who discontinued and subsequently restarted PrEP. Logistic regression analyses were conducted to determine factors associated with early PrEP discontinuation, PrEP use for ≥4 months and PrEP restart.

Results: PrEP use for ≤1 month was high (68.6%), although 27% returned and restarted PrEP; and 9% restarted more than once. Initiating PrEP at a mobile clinic (AOR 2.10, 95% CI 1.51 - 2.93) and having a partner known to be HIV negative or whose HIV status was unknown (AOR 7.11, 95% CI 1.45 - 34.23; AOR 6.90, 95% CI 1.44 - 33.09) were associated with PrEP use for ≤1 month. AGYW receiving injectable contraceptives were more likely to restart PrEP (AOR 1.61, 95% CI 1.10 - 2.35). Compared to those aged 15-17 years, participants 18 - 20 and 21 - 24 years were less likely to restart PrEP (AOR 0.51, 95% CI 0.35 - 0.74; AOR 0.60, 95%, CI 0.41 - 0.87), as were those initiating PrEP at a mobile clinic compared to a fixed facility (AOR 0.66, 95% CI 0.47 - 0.92).

Discussion: Although early PrEP discontinuation was high, it appears that PrEP use is frequently cyclical in nature. Further research is needed to determine if these cycles of PrEP correlate to periods of perceived or actual vulnerability to HIV, which may also be cyclical. PrEP delivery presents a unique opportunity to address multiple unmet health needs of young people.