Evaluation of the implantation site morphology in spontaneous abortion.

The aim of this study was the characterization of the implantation site through histological and immunohistochemical exams and the evaluation of the changes that appear in the pregnancies ended by spontaneous abortion compared to normal pregnancies ended by requested abortion. One hundred eight patients were divided in two groups: the study group that included 58 patients with spontaneous abortion and the control group that included 50 patients with requested abortion. There has been made uterine curettage in all the cases after a complete preoperative evaluation and the obtained product was sent for histopathological evaluation and immunohistochemical study using a VEGF antibody. Studying the histological sections, we noticed the vasculogenesis stages chronology and then according to the histological aspects of normal pregnancy we noticed the histological changes that occurred at the site of implantation in the cases with pathological pregnancies ended by miscarriage. Our results from this study seem to indicate a correlation between decidual vascular changes and the appearance of miscarriage. In pregnancies ended by miscarriage, we found delays in the trophoblast development according to the gestational age at which the event abortifacient happened. The study emphases the temporal differentiation of utero-placental angiogenesis comparing to villous vasculogenesis and angiogenesis in the first trimester miscarriage and normal pregnancy. At the control group, VEGF expression was positive in 88% of cases, while in the study group, pregnancies ended by spontaneous abortion, positive expression of VEGF was present in only 31% of cases. Our data suggest vascular disorders and are in concordance with other histological and ultrasound studies postulating the idea of a link between miscarriage and placental vascular bed pattern changes.