Mother-to-child transmission of HIV in Brazil during the years 2000 and 2001: results of a multi-centric study.

The objective of this study was to assess mother-to-child transmission rates of HIV in Brazil during the years 2000 and 2001, and to identify the maternal and neonatal variables that were associated with this transmission. It was a cross-sectional, observational study with retrospective data obtained from patient medical records. The children were followed at 63 medical sites situated in five geographical macro-regions of the country (20 States and the Federal Capital). Children enrolled were those that were born of HIV-infected mothers and it was necessary for the mothers to present documented proof of HIV-infection before or during pregnancy, at time of delivery or in the first three months after delivery. There were 2,924 children enrolled and mother-to-child transmission rates of HIV were 8.6% (95%CI: 7.2-10.2) for the year 2000 and 7.1% (95%CI: 5.8-8.6) for the year 2001. The following variables were associated with lower mother-to-child transmission rates of HIV: elective cesarean section, diagnosis of mother's infection before or during pregnancy, access to HIV viral load and T CD4+ lymphocyte count during prenatal care, greater birth weight and avoidance of breastfeeding.