Aberrant Expression of Transforming Growth Factor- $\beta$ _1 in Endometrium of Infertile Women During the Window of Implantation

Objective : TGF-_1 is a polypeptide which stimulates the growth of some mesenchymal cell types and inhibits the growth of epithelial cell types. Several studies have reported that TGF-_1 is present in the endometrial tissue and it is also involved in a variety of physiological processes such as the implantation of the embryo into the endometrium. However, the expression of endometrial TGF-_1 have not been well established in infertile women with endometriosis or hydrosalpinx having impaired endometrial receptivity. Therefore, the aim of this study was to determine the expression of endometrial TGF-_1 in infertile women and to compare it with that of fertile women during the window of implantation. Materials and Methods : Endometrial biopsies were performed during the window of implantation from 10 normal fertile women and 15 infertile women (5 unexplained infertility, 5 endometriosis and 5 tubal disease with hydrosalpinx). We performed immunohistochemistry using paraffin-embedded endometrial tissues. The staining intensity of TGF-_1-immunostained section was assessed by semi-quantitative histologic score (H-score=Sum[Pi x (i +1)]; i: intensity 0-3, Pi: %cells for each given intensity) of 100 cells. Results : In normal fertile women, the staining intensity of TGF-_1 in the glandular epithelium was higher than that of stromal cells. But the stromal cells showed an irregularly distributed positivity. In infertile women, their expression patterns were similar to those in fertile women. There was no statistically significant difference in the staining intensity of TGF-_1 between the glandular epithelium and stromal cell of women with unexplained infertility and that of fertile women. However, the staining intensity of TGF-_1 in the glandular epithelium and stromal cell of women with endometriosis or hydrosalpinx were significantly higher (p_1 in women with endometriosis or hydrosalpinx during the window of implantation may cause endometrial dysfunction during the implantation process such as endometrial-embryonic interactions and endometrial proteolytic activity.