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.

The authors have declared no competing interest.

This study was funded by the US National Institutes of Health (NIH) Eunice Kennedy Shriver National Institute of Child Health & Human Development and the National Institute for Allergy and Infectious Diseases under grant R01 HD103466 as well as the Fogarty International Center and National Institute of Mental Health, of the National Institutes of Health under Award Number D43 TW010543. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The funding source had no role in the design of this study nor any role during its execution, analyses, interpretation of the data, or decision to submit results.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee of South African Medical Research gave ethical approval for this work.

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

The data that support the findings of this study are owned by the KwaZulu-Natal Provincial Department of Health, and access is governed by policies and procedures in response to requests made directly to the Department. As such, the study teams will not have authority to release the data to the public or other data-sharing repositories. However, these data can be requested by the public through standardized request forms, which are then considered in an internal review procedure.