Engagement in antenatal and HIV care among pregnant women before and after Option B+ policy implementation in South Africa.

Background: Substantial gains have been made in South Africa in the prevention of vertical transmission of HIV over the past decade. Objectives: to determine whether engagement in antenatal and HIV care among pregnant Women Living with HIV (WLWH) differed after Option B+ implementation. Methods: We analysed cohort data from a pregnancy and birth defects surveillance system in KwaZulu-Natal (KZN). We report on two co-primary outcomes related to engagement in HIV care: 1) timing and number of ANC visits during the pregnancy period; and 2) timing of ART initiation (both self-reported ART use in interviews and observed initiation of treatment in maternal records). The association of policy era on the timing of ANC presentation was assessed using log-binomial regression modelling. We also report proportions initiating ART before or during pregnancy stratified by policy era. Results: Data from 40,357 women, including 16,016 (40%) WLWH were analysed. During the Option B+ era, 24% of pregnant WLWH attended their first antenatal care visit during the first trimester, compared to 16% during the Option B era (RR=1.52;95%CI=1.41-1.64). The proportion of women living with HIV who initiated ART prior to pregnancy was also higher during the Option B+ era compared to the Option B era, though this result was limited by missingness in the data. Conclusions: Engagement in antenatal and HIV care improved after Option B+ implementation. In the Option B+ era, South Africa has made significant progress towards the goal of eliminating mother-to-child transmission of HIV.