Umbilical Cord Structural Changes in Pregnancy-Induced Hypertension: Histological and Morphometric Insights

Introduction Pregnancy-induced hypertension (PIH) is a significant contributor to feto-maternal morbidity and mortality, especially in developing nations like India, where perinatal outcomes tend to be poor. This study was conducted to assess the potential histological and histomorphometric alterations in the umbilical cord of full-term mothers with normal pregnancies and those affected by PIH. Materials and methods In this observational, cross-sectional study, umbilical cords from 31 mothers in each of the two groups were selected according to specified inclusion and exclusion criteria: full-term mothers with normal pregnancies and those with PIH. Paraffin sections of the umbilical cords, approximately 5 µm thick, were prepared. Systematic random sampling was done to select samples for making slides and staining using hematoxylin & eosin (H&E) and periodic acid-Schiff (PAS) stains. The histology of the umbilical artery, vein, and Wharton's jelly was analyzed under a microscope. Histomorphometric parameters, specifically the wall thickness of the umbilical artery and vein, were measured. An unpaired Student's t-test was applied to determine if there was any statistically significant difference. A p-value of less than 0.05 was considered significant. Results On microscopic examination, the umbilical artery from the PIH Group showed a contracted lumen, thickening of the wall, increased hydropic changes, and deposition of fibrinoid material in the tunica intima and media. An umbilical vein from the PIH Group showed a dilated lumen, thinning of the wall, increased hydropic changes, increased intercellular space, contraction of cells, and disturbed architecture of smooth muscle cells (SMCs) and their nuclei, whereas Wharton's jelly from the PIH Group exhibited increased edema and decreased cellularity in comparison to the Control Group. In histomorphometric evaluation using an unpaired Student's t-test, the thickness of the wall of the umbilical artery in the PIH Group (798.715 ± 106.34 μm) was increased compared to the Control Group (718.206 ± 75.72 μm), with a p-value of 0.0002, and the results were extremely significant, whereas the thickness of the wall of the umbilical vein was reduced in the PIH Group (478.800 ± 76.65 μm) compared to the Control Group (667.506 ± 51.31 μm). The results were extremely significant, with a p-value of less than 0.0001. Conclusion Increased umbilical arterial wall thickness, decreased umbilical vein wall thickness, and decreased cellularity with edema of Wharton's jelly were observed, which could be a predictor of intrauterine growth restriction (IUGR) in term pre-eclamptic patients.