Policy change cut mother-to-child HIV but gaps remain

Preventing HIV passing from a pregnant person to their child is a major public health goal, and policy changes around antiretroviral therapy (ART) aim to make that happen. Nisha Jacob and colleagues examined how evolving guidelines for maternal ART in the Western Cape, South Africa, affected vertical transmission over eleven years. They focused on three policy periods: January–March 2010 when three-drug ART was accessible to people with CD4 counts <200 cells/µl; April 2010–April 2013 when eligibility widened to CD4 <350 cells/µl; and May 2013–December 2020 when lifelong ART was offered regardless of CD4 count. Using routine individuated public sector data, the team asked whether wider ART access led to fewer infant HIV infections and which groups still faced the highest risk. The study tracked pregnancies and child outcomes from 2010 through 2020, seeking to measure how many children became infected and how changes in policy and maternal treatment patterns influenced those outcomes. The research fills an important gap by using real-world health system records to show how policy decisions translated into results for families.

The researchers conducted a retrospective cohort study of 842,641 pregnancies from 2010–2020, assembling records of child HIV exposure, maternal ART, and child outcomes from administrative, laboratory and pharmacy data. They used multivariable logistic regression to explore associations with vertical transmission. Of all pregnancies, 17.1% (143,987/842,641) were recorded as HIV exposed; 16.3% (137,572/842,641) had a recorded child HIV outcome, and among those with outcome data 3,966 children (2.9%) were HIV positive by 24 months. The proportion of pregnant women living with HIV (WLWH) who began ART prior to pregnancy rose from 20.9% in 2010 to 71.1% in 2020. Among the 143,987 children known to be exposed, 32.0% had unknown HIV status and 2.1% were diagnosed with HIV by study closure. In 2020, HIV status was ascertained for 87.2% (16,908/19,382) of exposed children. Children born in policy period 3 were less likely to have HIV than those born in period 2 (adjusted odds ratio aOR 0.66; 95% CI 0.60–0.72), with this effect mediated through expanded ART access. Between 2017 and 2020, 16.5% of child HIV diagnoses came from pregnancies that lacked maternal HIV exposure records. Across all periods, young maternal age, no antenatal ART, previous tuberculosis and no records of antenatal visits were associated with higher chances of vertical transmission.

These findings show clear benefits from expanding ART access for pregnant people: more women were on treatment before pregnancy and fewer babies born to known-exposed pregnancies became HIV positive over time. At the same time, the study highlights persistent problems. A large share of exposed children still had unknown HIV status, and a meaningful number of infant infections arose from pregnancies without recorded maternal HIV exposure, suggesting missed testing or documentation gaps in the health system. Risk factors such as young maternal age, lack of antenatal ART, previous tuberculosis and absence of antenatal visits point to where services need strengthening. The authors’ use of routine public sector data demonstrates how health records can reveal both progress and remaining blind spots in vertical transmission prevention (VTP). The results argue for continued efforts to ensure universal maternal testing, complete follow-up of exposed infants, better documentation, and targeted support for higher-risk mothers so the momentum toward eliminating mother-to-child HIV transmission continues.