A Comparison of the Human Umbilical Cord's Histomorphometric and Histological Structure in Pregnant Diabetic and Non-Diabetic Women

Abstract

This study aimed to explore the histomorphometrical and histopathological alterations of umbilical cord (UC) vessels caused by gestational diabetes mellitus (GDM) and pre-gestational diabetes mellitus (PGDM). A total of thirty UC samples were obtained from full term pregnant women without any complications. Ten out of thirty UCs were obtained from non-diabetic pregnant women (normal group), 10 from GDM and 10 from PGDM pregnant women. Segments from the placental attachment, center and fetal side of UCs were taken for each group. These segments were processed for paraffin blocks, sectioned, and stained with H&E, Masson trichrome (MT) and Periodic Acid Shift (PAS). The results of the histomorphometric study showed no significant differences in the UC mean weight among these three groups. In three different segments, GDM resulted in a significant decrease in artery and vein wall thickness compared to the control group. GDM and PGDM resulted in a non-significant difference in the diameter of artery and vein in fetal segment, the vein in placental segment, and artery in the central segment compared with normal. All the UCs in the three groups contained two arteries and one vein but only one cord recorded in the GDM group contained one artery and one vein. Histological study of diabetic UC segments showed extravasation of blood, artery discordance, degeneration of Warton’s jelly (WJ) fibers with formation of honeycomb like empty spaces, formation of multiple spaces between smooth muscle cells of tunica media and detachment of the umbilical arteries from surrounding WJ. In both diabetic groups, there was a marked decrease in collagen fibers in tunica intima and media with their irregular arrangement in both arteries and vein especially in placental segment. The results also showed there was a rich carbohydrate content in the intima and media in all three groups. In conclusion, the current results proved that GDM and PGDM have an adverse effect on the structure of UC and its vessels.

Keywords: Umbilical cord; Diabetes mellitus; Histological study; Special stains; Blood vessels

DOI: 10.7176/JBAH/13-6-04

Publication date: April 30^th 2023