Objective: The purpose of this study was to evaluate the presence of HIV-1 in cervico-vaginal secretions of pregnant as compared to non-pregnant HIV-seropositive women.
Patients and methods: We compared 43 known HIV seropositive pregnant patients versus 241 age-matched (± 2 years) control non-pregnant HIV-seropositive subjects. In pregnant patients blood and cervico-vaginal samples were obtained during each trimester of pregnancy. In control subjects the same samples were obtained at enrolment. HIV-1 RNA was measured in plasma; proviral HIV-1 DNA, cell-associated and cell-free HIV-1 RNA in cervico-vaginal secretion by competitive polymerase chain reaction (cRT-PCR) and reverse transcriptase PCR.
Results: The genital shedding of HIV-DNA (22/43 as compared to 79/241, p = 0.02), and cell-free HIV-RNA detection (26/43 as compared to 72/241, p < .001) was more common in first-trimester pregnant than in non pregnant women. Pregnancy correlated with a significant positive trend in the cervico-vaginal load of HIV-DNA (Spearman Rho= 0.149, p= 0.012), and cell-free HIV-RNA (Spearman Rho= 0.253, p < .001), but not of HIV-RNA transcripts (Spearman Rho = 0.06, p= 0.31). After correction for potential confounders, first trimester pregnant women had increased rates of genital HIV- DNA (odds ratio = 1.94, 95% confidence interval = 1.01 3.78) and cell-free HIV-RNA (odds ratio = 4.07, 95% confidence interval = 1.97 8.41) detection compared to nonpregnant controls.
Conclusion: The shedding of genital HIV was increased in pregnant compared to non pregnant subjects, even in patients with undetectable viremia. In this low-risk HIV-positive population the risks of vertical or horizontal transmissions should not be underestimated.