Ultrastructural and immunohistochemical evaluation of endometrial tissues of infertile women with recurrent implantation failure

To evaluate endometrial tissues of fertile women and the women with recurrent implantation failure (RIF) analyzed by using transmission electron microscopy (TEM) and MUC1 immunohistochemistry. In this study, 23 patients with RIF and 11 fertile women participated. Endometrial tissue samples were examined by light and electron microscopes. Additionaly, MUC1 immunoreactivity was evaluated. Electron microscopic examination of the endometrial surface epithelial cells of the recurrent implantation failure revealed lots of cytoplasmic extensions containing secretory vacuoles and irregular microvilli. Furthermore, most of the endometrial cells exhibited secretory vacuoles in the supranuclear region. Immunoreactivity of MUC1 was detected weakly in the luminal epithelium of the control group whereas the staining intensity was conspicuous in RIF group. Significant differences between the groups with respect to glandular epithelium were found. Endometrial tissues of both fertile women and women with RIF were thought to be important in regulating the stage for embryo implantation. Further studies should be done to have a better understanding of factors involved in the establishment of endometrial receptivity.