The spread of HIV-1 infection among women of childbearing age has led to increasing numbers of children at risk of vertical transmission. This study aimed to assess child outcomes among HIV-positive (n=19) and AIDS (n=22) mothers from Central West Brazil. CD4(+) T-cell counts (FACScount, BD) and viral loads (HIV-1 RT-PCR, Amplicor HIV-1 Monitor Roche) were assessed at delivery and during the first 6 months of life. Heteroduplex mobility assay identified env and gag HIV-1 subtypes. Frequencies and medians were calculated. HIV-positive and AIDS mothers did not differ with regard to age, antiretroviral prophylaxis, parity and viral load. AIDS mothers had lower CD4(+) T-cell counts. One vertical transmission and a neonatal death were observed. Gestational age, gender and oral zidovudine prophylaxis were similar regardless of maternal clinical status. Infants born to AIDS mothers had lower birthweight and shorter time to seroreversion. Eight infants were lost to follow-up, and two were breastfed due to delayed maternal diagnosis. HIV-1 B(env)/B(gag) subtype were 75.6%; discordant B(env)/F(gag) were 12.2%. Exposed uninfected infants born to AIDS mothers with lower CD4(+) T-cell counts seroreverted earlier than infants born to asymptomatic HIV-positive mothers. It is possible that maternal immunological status may impact on the time to seroreversion.