Objective: To describe the management of a population of human immunodeficiency virus (HIV)-infected pregnant women in Latin America and the Caribbean, and to assess factors associated with maternal viral load of 1,000 copies/mL or more and with infant HIV-1 infection.
Methods: Eligibility criteria were enrollment in the prospective cohort study as of March 2006; delivery of a liveborn, singleton infant; and completion of the 6-month postpartum or postnatal visit.
Results: Of 955 women enrolled in Argentina, the Bahamas, Brazil, and Mexico, 770 mother-infant pairs were eligible. At enrollment, most women were relatively healthy (87% asymptomatic, 59% with viral load less than 1,000 copies/mL, 62% with CD4(+)% of 25% or more). Most (99%) received antiretrovirals during pregnancy (56% prophylaxis, 44% treatment), and 38% delivered by cesarean before labor and before ruptured membranes. Only 18% of women had a viral load of 1,000 copies/mL or more after delivery (associated in adjusted analyses with receipt of antiretrovirals at conception, CD4(+)% [lower], viral load [higher], and country at enrollment, enrollment late in pregnancy, and inversely related to antiretroviral regimen [two nucleoside or nucleotide analogue reverse transcriptase inhibitors plus one nonnucleoside reverse transcriptase inhibitor] during pregnancy). None of the infants breastfed, and all received antiretroviral prophylaxis. Seven infants became infected (0.91%; 95% confidence interval 0.37-1.86). Low birth weight infants and those whose mothers had a low CD4(+)% at hospital discharge after delivery and were not receiving antiretrovirals at enrollment were at higher risk of HIV infection.
Conclusion: Only a minority of women had a viral load of 1,000 copies/mL or more around delivery, and mother-to-child transmission of HIV occurred rarely (1%).