The present study includes assessment of morphological and ultrastructural differences in the afterbirth from pregnancies complicated by fetal hypertrophy (9 cases- a study group) as opposed to those from full-term pregnancies (10 cases - a control group). Abnormalities were evaluated macroscopically and on light and transmission electron microscopy. Macroscopic placental examination showed no evidence of focal abnormalities. Light microscopy (histopathological evaluation) of samples from hypotrophic pregnancies showed a decreased intervillous space with a simultaneous increase in the size of the villi, congestion of the villi and intervillous space. Additionally, moderate and severe fibrosis was noted. Transmission electron microscopy of the majority of samples showed oedema of the villous endothelial cells as well as exfoliation of the cells from the basal membrane and filling in of the new space by collagen fibres. Rugosity and thickening of the basal membrane was present. In severe endothelial exfoliation an increased number of lysosomes in the trophoblast cells directed towards the intervillous space. In the group of placentas from full-term pregnancies, moderate oedema was found in the endothelial cells, and in some cases mild trophoblast vacuolisation was also present.

Keywords: Placenta, placental morphology, fetal hypertrophy, ultrastructure, transmission electron microscopy