Proceedings from the 12th Rochester Trophoblast Conference, held in Autumn 1992 in Rochester, New York. The first part of the book addresses the role of the placenta in the transmission of the HIV infection, the central focus of the Conference. Other pre-natal infections, including CMV, Vaccina, Parvovirus, Syphillis, and Herpes Simplex, are then considered, and their implications for perinatal health investigated. The importance of cell regulation is also discussed, exploring the controlling factors which modulate the placental cell membrane and metabolic functions, such as genetic imprinting, the regulation of arachidonic acid cascade, autocrine role for human chorionic gonadotropin, biochemical screening for Down's Syndrome, the role of growth factors and interferon, the autoregulation of gas exchange, and the role of uterine cytokines. HENRY THIEDE is Professor of Obstetrics and Gynecology at the University of Rochester.RICHARD K. MILLERteaches in the University of Rochester Medical Center.