In gestational diabetes both the foetus and placenta experiences a diversity of structural and functional changes. While the changes in the placenta such as placental size, oedema, associated placental abnormalities and microscopic changes such as syncytial knots have been extensively studied, the information on the umbilical cord morphometry is scanty and hence is an area of interest.
Objective: To study the various umbilical cord morphometric indices in pregnancies complicated by abnormalities of glucose metabolism of varying degrees.
Methods: Initial screening for gestational diabetes was done using standard two step protocol (spot test / glucose challenge test - GCT and glucose tolerance test - GTT if spot test result was abnormal). Umbilical Cord Cross Sectional Area (UCCSA), Umbilical Artery Cross Sectional Area (UACSA), Umbilical Vein Cross Sectional Area (UVCSA) and Wharton's Jelly Area (WJA) were measured in pregnant woman after 34 weeks of gestation at the time of third trimester scan. Scans were repeated every two weeks till the woman delivered.
Results: Out of 250 patients recruited for the study, there were 54 patients of abnormal spot test. Among them only 21 had true Gestational Diabetes (GDM) and rest 33 had impaired glucose tolerance (IGT). Umbilical artery and vein area, Wharton’s jelly area and total area were significantly higher in GDM group compared to normal controls. Sub-analysis indicated that these values are also higher in IGT group followed by abnormal GCT group compared to normal controls indicating that glucose abnormalities of varying degrees affects these measurements.
Conclusion: There is a positive association between abnormal glucose metabolism and umbilical cord parameters such as artery and vein area, Wharton’s Jelly content and total cord area. These changes may occur to ensure enough nutrient supply to the foetus, which has as such increased body composition which is a response to maternal hyperglycemia.