Effect of gestational diabetes mellitus and its management on the histological and histomorphometric structure of umbilical cord: a comparative study

The umbilical cord lacks vasavasorum and is prone for hypoxic injuries. Gestational diabetes mellitus (GDM) causes structural changes with in umbilical cord blood vessels. Knowledge of which would be helpful for the gynecologist and obstetricians to assess the prognosis and prevent the complications. The present study was concentrated from December 2016 to December 2019 on 50 normal and 56 GDM umbilical cords. GDM group included 23 GDM mothers managed by diet (GDM-Diet) and 33 GDM mothers managed by drugs (GDM-Drug). Placentas along with the attached umbilical cords were collected and stored in 10% formaline. Tissue processing, slide preparation and stainings were done using standard protocols. A significant reduction was observed in the number of Hoboken nodules of umbilical arteries of GDM-Diet. Reduction of myofibroblasts with an increase in the empty spaces was observed in the Wharton's jelly of both GDM cases. Similarly, smooth muscle disintegration and migration of smooth muscles to intima was significantly higher in GDM umbilical arteries and veins than normal umbilical vessels. The total wall thickness and tunica media was significantly thicker in the umbilical arteries of GDM-Drug group only. The umbilical venous lumen was found significantly wider in GDM groups compared to normal. The elastin fibers were significantly found reduced in the tunics of umbilical arteries and veins in GDM. However, a significant difference in these parameters was not observed between the GDM-Diet and GDM-Drug groups except for total wall and tunica media thickness of umbilical arteries.