To assess whether Candida species can penetrate intact fetal membranes under in vitro conditions, Candida albicans, Candida tropicalis, Candida guil-liermondii, Candida pseudotropicalis and Candida glabrata were inoculated onto the surface of the maternal side of the membranes obtained from 4 pregnant women undergoing repeat cesarean section. After incubation under culture conditions, membranes were evaluated by histological examination. C.albicans inoculated onto the maternal side penetrated and passed to the fetal side and caused some degeneration of the structure of the membrane epithelium. The other four Candida species grew heavily on the maternal surface but did not penetrate and invade the membranes. This effect of C. albicans on fetal membranes may explain the potential mechanism in the development of Candida infections of the amniotic fluid, fetal membranes and possibly the fetus.