The South African National HIV Pregnancy Cohort: evaluating continuity of care among women living with HIV.

BACKGROUND: South Africa is home to more people living with HIV than any other country, including nearly one in three pregnant women attending antenatal care. Access to antiretroviral therapy (ART) has increased substantially since the start of the national ART program in 2004, with > 95% ART coverage during pregnancy and delivery, and vertical transmission of HIV greatly reduced. However, women who initiate ART during pregnancy are at heightened risk of dropping out of care, particularly after delivery, leading to the potential for viral transmission, morbidity and mortality. It is difficult to evaluate the success of policies of expanded access to ART care, and assess continuity of care, due to the lack of a national longitudinal HIV care database. Also, patient movement between unlinked facilities. For the first time on a national level, we propose to utilize routinely-collected laboratory data to develop and validate a cohort of pregnant women living with HIV in South Africa in a way that is uniquely robust to facility transfer. METHODS: Using laboratory test data matched to facility type, we will identify entry to antenatal care to build the cohort, then describe key treatment milestones, including 1) engagement in antenatal care, 2) initiation of ART, 3) HIV viremia, and 4) continuity of HIV care in the postpartum period. Second, we will measure the effect of system-wide factors impacting continuity of care among pregnant women. We will assess policies of expanded treatment access on continuity of care using regression-discontinuity analyses. We then will assess mobility and its effect on continuity of care during and after pregnancy. Third, we will identify individual-level risk factors for loss from HIV care in order to develop targeted interventions to improve engagement in HIV care. DISCUSSION: This work will create the world's largest national cohort of pregnant women living with HIV. This novel cohort will be a powerful tool available to policymakers, clinicians and researchers for improving our understanding of engagement in care among pregnant women in South Africa and assessing the performance of the South African national ART program in caring for pregnant women living with HIV. TRIAL REGISTRATION: N/A (not a clinical trial).