Comparative Analysis of the Villous Abnormalities of Placentae in Pregnancy Induced Hypertension with that of Normal Pregnancy

Background: Hypertension is one of the common complications seen in pregnancies in the developing countries which contribute significantly to the maternal and fetal morbidity and mortality.

Objective: The present study was undertaken to analyse the histomorphologic changes of the placenta in pregnancy induced hypertension by looking for any significant differences in the villous abnormalities between the PIH group and the control group.

Study Design: Placentae from fifty mothers with uncomplicated pregnancy and fifty mothers with pregnancy induced hypertension (PIH) were divided as control and study group respectively. The microscopic features were compared between the control and PIH group.

Place and Duration of Study: Department of Pathology, MVJ Medical College and Research Hospital, Bangalore, between 2011 and 2013.

Methodology: The microscopic features such as syncytial knots, vasculo-syncytial membrane (VSM), fibrinoid necrosis, basement membrane thickening and villous stromal fibrosis were compared between the placentae of the control and the PIH group. About four hundred villi were counted for each placenta and the mean was calculated for all the microscopic features. A ‘p’ value less than 0.05 was taken to be statistically significant. Gross abnormalities such as infarction and calcification were noted.

Results: The villous abnormalities observed in the study (PIH) group were increased syncytial knots (66%), paucity of vasculo-syncytial membrane (80%), fibrinoid necrosis (100%), basement membrane thickening (76%) and villous stromal fibrosis (90%). A ‘p’ value <0.001 of statistical significance was noted in the microscopic abnormalities of the villi in the placentae of the PIH group.

Conclusion: A highly significant increase in the villous abnormalities in the PIH group was found as compared to full term placenta which could attribute towards reduced uteroplacental flow.