Anti-retroviral therapy failure in HIV-1 infected pregnant women and its associated risk of HIV transmission.

BACKGROUND The HIV perinatal transmission in India even after interventions is still high. The anti-retroviral therapy failure rate and the risk of HIV vertical transmission to infants from women with failed treatment during pregnancy also largely remains unevaluated. METHODS This is a prospective, observational and follow-up study of 18 months to determine the association of ART failure in pregnant women and the subsequent risk of HIV transmission to their infants. A total of 81 mothers were evaluated for ART success/failure by analysing their viral loads. RESULTS Analyses revealed that a high percentage (19.75%) of women on ART had high viral loads, while the overall HIV transmission rate to the infants was 8.64%. The rate of transmission from women with high viral load was significantly high compared to women with low viral load (37.5% vs. 1.54%; p = 0.0015). CD4 level was not associated with HIV transmission. However, CD4 levels in women, who had successful or failed ART, were significantly different (p = 0.0031). Factors such as mother's age, baby's sex and weight as well as delivery mode were not associated with HIV transmission, however, breastfeeding and viral loads were found to be independently associated with HIV transmission to the neonates. CONCLUSIONS This study highlights that a significant proportion of women on ART had impaired viral load control. The rate of HIV transmission to infants was also significantly high among these women. This warrants viral load monitoring of HIV infected women to reduce the overall transmission to the infants.