Histologic and morphometric study of human placenta in gestational diabetes mellitus

The aim was to study morphometry, site of umbilical cord insertion and histological changes in placentae of women with gestational diabetes mellitus and compare the results with those of normal pregnancies and observe the perinatal outcome.

It was an observational, correlational study of 130 placenta specimens collected from labour room and operation theatre of Department of Gynaecology & Obstetrics, Institute of Post Graduate Medical Education and Research, Kolkata. The subjects were mothers who attended antenatal clinic of the hospital regularly and delivered their babies in the same hospital. Cases were selected randomly, and divided in two groups: group A consisted of mothers having normal, uncomplicated pregnancy, group B consisted of mothers whose pregnancies were complicated by gestational diabetes mellitus. Morphometry, site of umbilical cord insertion and histological changes in placentae of all women were recorded. Perinatal outcome of the cases were also registered. The statistical methods used were chi-square test and Mann-Whitney U test.

It was observed that the placentae of diabetic mothers were significantly bigger in size, weight, volume, area, thickness, diameter and circumference than those of normal mothers. Also, in diabetic mothers, there was significant increase in villous oedema, fibrin deposition, calcification and congestion of blood vessels. These placental changes were significantly correlated with birth weights of babies. Out of 70 mothers in Group B, 65 had live births, 5 had stillborn babies.

Placentae of women with GDM showed several changes that may be associated with impaired functioning, leading to bad perinatal outcome.