Morphometric investigations of terminal villi of diabetic placentas in relation to the White classification of diabetes mellitus

In this morphometric study, terminal villi of 22 placentas of maternal diabetes mellitus were compared with the results in terminal villi of 22 normal placentas. The results demonstrate that there is a distinct retardation in maturation, statistically significant with bigger cross sectional surfaces of the terminal villi, particularly, when classified in 3000 mu2-steps, the number of the villous vessels and number of epithelial plates. Only slightly decreased in diabetic placentas is the villous vessels cross sectional surface as well as the degree of vascularization. The correlation between the degree of histometric changes and the severity and duration of the disease was separately investigated (classification was done according to White). It could be shown, that the degree of morphologic changes in the terminal villi does not run strictly parallel to the severity and duration of diabetes. The retardation in maturation of the terminal villi increases from White group A to C. In White group D, which is the most severe stage of diabetes mellitus which we investigated, the values of measured parameters are close to the normal placentas. This observation is interpreted as a compensatory reaction of the fetal organ placenta to the reduction in utero placental blood flow in diabetes caused by the diabetic angiopathy.