RESUMO
This study was conducted to evaluate the value of histomorphological features of chorionic villi, such as villous size, shape, vascularity, trophoblastic proliferation and trophoblastic pseudoinclusions for the prediction of chromosomal abnormality. A review of all spontaneous abortions between 1995-2000 yielded 115 cases in which maternal history indicated no more than one prior spontaneous abortion and a reliable date of last menstrual period. Molar pregnancies were excluded. Cell culture for chromosomal analysis was made of the tissues of non-maternal origin. The remaining material was fixed in 4% formalin and embedded in paraffin. Sections 4 microm thick, of the chorionic villi were made and stained with haematoxylin and eosin. The histomorphologic criteria revealed sensitivity, specificity and accuracy of 58.3%, 89.1% and 75.6%, respectively. The most frequent features were: intervillous fibrin, villous edema, increased villous size, villous ramifications and reduced vascularity. Induced abortions showed less villous fibrohyalinization and more increased vascularity than spontaneous abortions. The histopathologic examination is of great help in assessing whether an abortion is chromosomally normal or abnormal