Maternal vascular lesions in pre-eclampsia and intrauterine growth retardation: light microscopy and immunofluorescence.

Placental bed biopsies were performed during caesarean section in a series of 137 patients. Analysis of the morphological findings confirms that vascular physiological changes were reduced in pre-eclampsia and in normotensive intrauterine growth retardation. In pre-eclampsia, acute atherosis in the decidual segments of uteroplacental arteries was a prominent feature. Intimal thickenings of the myometrial segments of the uteromaternal arteries were also noted. Normotensive intrauterine growth retardation cases were characterized by intimal thickenings of the myometrial segments of the uteroplacental arteries. Immunofluorescent investigations have demonstrated that the deep vascular stenoses were not associated with immunoglobulin deposition while in distal arterial segments displaying acute atherosis a positive immunofluorescence for IgG and fibrin and, more irregularly, for C'3 and IgM could be noted. These findings lead us to suggest that an immunological mechanism may be involved in the pathogenesis of acute atherosis.