Type 1, type 2 and gestational diabetes mellitus impact on the placental structure.

Diabetes is the most common medical complication associated with pregnancy. During pregnancy complicated with maternal diabetes (DM), the placenta suffers certain pathological, functional and structural changes. DM was correlated with a rapid progressive microangiopathy and this, in turn, may be associated with capillary hypertension and changes in capillary permeability. The objective of the study is to identify the clinical correlations with influence on gestation in general, and on the placental structure in particular, in pregnancy associated with type 1 (T1DM), type 2 (T2DM) and gestational diabetes mellitus (GDM). The impact of the clinical conditions associated with DM on placenta has been analyzed and correlated with the ultrasound (US), morphological, histological and immunohistochemical study of the placental structure. Preexisting maternal hypertension, preeclampsia and obesity were the main associated conditions. The US examination of placental characteristics revealed an increase in placental thickness in the second trimester. The macroscopic analysis showed that the placentas of women with diabetes are heavier. Gross pathological analysis of maternal and fetal surfaces of placentas revealed subcortical or basal plaque fibrin deposition, and placental infarction or intervillous thrombosis. From the microscopic point of view, the findings include fibrinoid necrosis, intervillous fibrosis, focal hyaline degeneration, villous immaturity, chorangiosis, placental calcifications, placental infarction or decidual vasculopathy. Maternal hypertensive disorders amplify the spectrum of morphological changes in the placenta. Placental immaturity and villous capillary dysfunction are characterized by increased angiogenesis and enhanced vascular permeability. The diabetic placenta does not show specific changes, but different associations may be a diabetic pathological pattern influenced by associated conditions, especially preeclampsia, obesity, dyslipidemias and the lack of euglycemia during pregnancy. [ABSTRACT FROM AUTHOR]