Recent alcohol use is associated with increased Pre-exposure Prophylaxis (PrEP) continuation and adherence among pregnant and post-partum women in South Africa

Background: South African women experience high levels of alcohol use and HIV infection during the perinatal period. Oral pre-exposure prophylaxis (PrEP) is highly effective at reducing HIV risk. We examined associations between alcohol use and PrEP use during pregnancy and postpartum. Methods: PrEP-PP is a prospective observational cohort of 1200 HIV-negative pregnant women enrolled at first antenatal care visit and followed through 12 months postpartum in Cape Town, South Africa. The analytic sample comprised pregnant women who initiated PrEP at baseline and were not censored from study follow-up prior to 3 month follow-up. We examined associations between any or hazardous alcohol use (AUDIT-C score ->3) in the year prior to pregnancy and PrEP continuation and adherence during pregnancy (self-report of missing <2 doses in past 7 days, and biomarker-confirmed with tenofovir diphosphate in dried blood spots). Results: Of 943 women on PrEP (median age 26 years), 50% reported alcohol use prior to pregnancy and 33% reported hazardous use. At 3 month follow-up, 58% of women were still using PrEP; 41% reported recent adherence and 23% were biomarker-confirmed adherent. In multivariable models, hazardous alcohol use was associated with increased odds of continuing PrEP (aOR=1.54, 95% CI: 1.16-2.06), self-reported PrEP adherence (aOR=1.41, 95% CI: 1.07- 1.87), and biomarker- confirmed PrEP adherence (aOR=1.35 95% CI: 0.98, 1.87). Associations were similar in models of any alcohol use and PrEP continuation/adherence. Pregnant and postpartum women who reported recent alcohol use had increased odds of continuing to take PrEP, indicating that higher risk women may continue on oral PrEP.