[Vascular lesions of the endometrium in spontaneous abortion]

On the basis of a histological study of vascular lesions of the endometrium following 108 cases of spontaneous abortion, the authors propose the following conclusions: 1) In the first six weeks of pregnancy, early abortion results more often from a primary ovular defect than from any abnormality in the maternal environment, of endogenous or exogenous origin and capable of resulting in a lesion of the endometrium or its vascularisation. The structure of the walls of the spiral arteries of pregnancy is almost invariably normal. 2) By contrast, in late abortions, arterial lesions--and in particular fibrosis--may play a role. This occurs however when the basal arteries with a well-differentiated elastic structure are involved. The spiral arteries of pregnancy and the utero-placentar arteries are involved only by lesions of vasculitis secondary to inflammatory phenomena as a result of retention of the products of conception or by pseudo-atheromatous lesions resulting from the deposition of degenerated cyto-trophoblastic elements, but never from true arteriosclerotic lesions.