Prevalence and risk factors of detectable HIV viral load among pregnant women with HIV infection seeking antenatal care in Southern Malawi.

We evaluated detectable viral load (VL) in pregnant women established on antiretroviral therapy (ART) for at least 6 months before conception and those self-reported as ART naïve at first antenatal care (ANC) at two government clinics in Southern Malawi. We used logistic regression to identify the predictors of detectable viral load (VL), defined as any measure greater than 400 copies/ml. Of 816 women, 67.9% were established on ART and 32.1% self-reported as ART naïve. Among women established on ART, 10.8% had detectable VL and 9.9% had VL >1000 copies/ml (WHO criteria for virological failure). In adjusted analysis, among women established on ART, virological failure was associated with younger age ( p = .02), "being single/widowed" ( p  = 0.001) and no previous deliveries ( p = .05). One fifth of women who reported to be ART-naive were found to have an undetectable VL at first ANC. None of the demographic factors could significantly differentiate those with high versus low VL in the ART-naïve sub-sample. In this cohort, approximately 90% of women who had initiated ART prior to conception had an undetectable VL at first ANC. This demonstrates good success of the ART program but identifies high risk populations that require additional support.