Chorioamnionitis is associated with placental transmission of human immunodeficiency virus-1 subtype E in the early gestational period

The frequency and the cellular basis for HIV-1 transmission from mother to child in the early gestational period are poorly understood. We compared the placentas of 24 women seropositive for HIV-1 subtype E and who had not received any antiretroviral drugs, to placentas of 25 seronegative women. All placentas were obtained during therapeutic abortion at 6–23 weeks gestation. Placentas and fetal organs were examined by routine light microscopy, immunostaining for p24 capsid protein, and in situ PCR to localize which cells were infected with HIV-1 subtype E. The number of previous abortions was not a factor in placental HIV infection since this number was higher in seronegative women (P