Study Findings Show High Oral PrEP Initiation in Adolescent Girls, Young Women Who Are Pregnant, Postpartum

Adolescent girls and young women (AGYW) aged 16 to 24 years in South Africa are at risk of acquiring HIV, with AGYW making up 25% of all acute HIV infections in sub-Saharan Africa. In addition, the risk of contracting HIV is higher for AGYW during pregnancy and postpartum periods. Oral pre-exposure prophylaxis (PrEP) is an antiretroviral medication that can be taken daily by individuals who are HIV-negative before exposure to help prevent infection, but strong adherence is necessary for PrEP to be effective.

Authors of a study published in Frontiers Reproductive Health evaluated PrEP initiation and continuation during a 6 month period in AGYW. Further, the study investigators examined the association between baseline HIV risk and PrEP delivery outcomes in AGYW who are pregnant or postpartum.

For this cohort study, staff administered a baseline survey to collect participant demographic information, clinical characteristics, and behavioral HIV risk factors using an online application. PrEP initiation was defined as accepting and receiving a PrEP prescription at the baseline visit—which was also their first antenatal care (ANC) visit—and PrEP continuation was defined as receiving a PrEP prescription at each study visit after the baseline visit among those who initiated PrEP at baseline.

Follow-up visits were conducted at 1, 3, and 6 months. The 1-month visit provided participants with a PrEP refill, and at the 3- and 6-month visits, patients completed follow-up surveys regardless of their PrEP use throughout the trial. In addition, dried blood spot (DBS) samples were collected from those who reported taking PrEP in the last 30 days during follow-up, which detected tenofovir diphosphate (TFV-DP) concentration levels.

The study included 486 women who were pregnant and were negative for both HIV and hepatitis B surface antigen. Approximately 16% (n = 77) of the enrolled patients were adolescents (aged 16 to 18 years) and 84% (n = 409) were young women (aged 19 to 24 years). Patients underwent a point-of-care testing for sexually transmitted infections (STIs) and those who were diagnosed with an STI were provided with treatment. Regardless of responses to behavioral HIV risk factors and STI factors, the participants underwent HIV testing and counseling with an offer to start using PrEP as part of a combined prevention strategy. Participants who were interested in starting to use PrEP had their blood tested to confirm whether their baseline levels met clinical eligibility for PrEP or not.

The results indicate that AGYW were found to have a higher oral PrEP initiation, with approximately 33% of these women continuing PrEP use through 6 months. Among those who discontinued the use of PrEP, 6% of AGYW had restarted use at 6 months. Of the 83% (n = 403) who initiated PrEP, 63% (n = 253) had continued using PrEP at the 1-month follow-up, 54% (n = 212) continued at 3 months, and 39% (n = 149) continued at 6 months. These AGYW had similar PrEP uptake and continuation prevalence across the cascade. In addition, approximately 27% (n = 110) of AGYW had consistently attended the follow-up visits through 6 months after initiating PrEP, and 6% (n = 25) missed either the 1- or 3-month visit but restarted on PrEP at 6 months.

Of the participants who had DBS samples collected and analyzed, 6% (n = 10) were found to have high adherence (~7 doses per week), 20% (n = 35) had medium adherence (~2 to 5 doses per week), 23% (n = 40) had low adherence (<2 doses per week), and 51% (n =90) either had unquantifiable TFV-DP concentration levels or did not report using PrEP in the last 30 days during the 3-month visit. In the last 30 days during the 6-month visit, 1% (n = 1) were found to have high adherence, 5% (n = 5) had medium adherence, 14% (n = 15) had low adherence, and 80% (n = 80) had unquantifiable TFV-DP concentration levels or did not report using PrEP.

In addition, 96% of pregnant AGYW were sexually active at baseline. Approximately 68% and 71% continued to be sexually active at the 3- and 6-month follow-ups, respectively. A higher proportion of adolescent girls (75%) reported sexual abstinence during the postpartum period compared to young women (52%); however, by 6 months, the frequency of sexual activity during the postpartum period was similar for both groups. Further, adolescent girls with no perceived HIV risk reported sexual abstinence at 3 months (55%), whereas young girls with no perceived HIV risk had a lower rate of sexual abstinence (28%).

Although the proportions of AGYW who were pregnant and postpartum that initiated PrEP at baseline were similar (82% vs 83%, respectively), the percentage of continuation at 1 month (56% vs 66%, respectively), 3 months (45% vs 59%, respectively), and 6 months (34% vs 42%, respectively) was higher among those with greater HIV baseline risk scores compared with those with lower risk scores; however, the proportion of those with any TFV-DP concentration levels detected in DBS samples was similar at 3 months (48% vs 49%, respectively) and 6 months (14% vs 22%, respectively).

Limitations of the study include the collection of PrEP-PP data from 1 urban ANC clinic resulting in a lack of generalizability and potential self-report errors due to social desirability bias. Adherence levels were marked by the investigators as missing or unknown for those who reported using PrEP but did not have their DBS analyzed later in the study. Further, low adherence to PrEP among AGYW could be due to changing HIV risks.

The findings suggest the existence of key barriers in HIV prevention methods for AGYW who began ANC visits later and had a high burden of untreated STIs, according to the study authors. Further, they recommend that HIV and PrEP counseling should be integrated into ante- and postpartum care and community delivery to simplify PrEP delivery among women who are pregnant.

Reference

Khadka N, Gorbach PM, Nyemba D, et al. Evaluating the use of oral pre-exposure prophylaxis among pregnant and postpartum adolescent girls and young women in Cape Town, South Africa. Front Reprod Health. 2023;5. doi: 10.3389/frph.2023.1224474