Morphological aspects of the placenta in HIV pregnancies.

Forty-nine placentae from HIV-seropositive mothers were collected in various hospitals in France and Belgium. Twenty [corrected] placentae with seven fetuses from interrupted pregnancies and 29 [corrected] placentae from spontaneous deliveries, including two stillborns and a set of twins, were studied morphologically. No significant abnormalities were observed in the aborted material. The placentae corresponding to deliveries presented no significant gross abnormalities but the ratio of fetal to placental weight was significantly decreased in the study group compared with the control group (6.13 versus 7.41; P less than 0.001), associated with a congestive and mature aspect of the parenchyma. Histologically a high incidence of chorioamnionitis (43 per cent) was found, contrasting with the absence of villitis. A relative villous hypercellularity was observed in the study group compared with the control group. Ultrastructural studies of 13 placentae corresponding to gestations of 10 to 40 weeks are presented. In six cases, retrovirus-like particles were found at various sites, such as villous fibroblasts, syncytiotrophoblast and endothelial cells, and in the free membranes.