The numbers of HIV-infected women initiating antiretroviral therapy (ART) in pregnancy are increasing rapidly with global policy changes. There are widespread concerns about ART adherence during pregnancy and postpartum but few data on viral suppression (VS) over time in these populations.
We followed a cohort of 523 women in Cape Town, South Africa initiating ART in pregnancy (once daily tenofovir 300mg, emtracitabine 200mg and efavirenz 600mg) and achieving VS (<50 copies/mL). Participants provided specimens through 12 months postpartum for batched viral load (VL) testing separate from routine care. Analyses described the incidence of major (>1000 copies/mL) and minor (50-1000 copies/mL) viraemic episodes (VE) and factors associated with major VE.
In the cohort (median age, 28 years; median pre-ART VL, 3.99 copies/mL; 3% previously defaulted ART; 24% with previous exposure to short-course antiretrovirals) the median time of follow-up from VS was 322 days. Overall, 70% maintained VS throughout follow-up, 8% experienced minor VE only, and at least one major VE was documented in 22% of women. In women with VE, peak viremia (median, 3.79 log10 copies/mL) was linearly related to pre-ART VL. The incidence of major VE after initial VS was independently associated with younger age, ART initiation during the third trimester, previous defaulting on ART and postpartum follow-up.
Viraemia appears to occur frequently, particularly postpartum, among HIV-infected women after initial VS in this setting. More intensive VL monitoring is warranted in this population while the immediate causes and long-term implications of VE require investigation.