Expression of αvβ3 integrin, leukemia inhibitory factor and pinopodes as markers of endometrial receptivity in idiopathic recurrent spontaneous miscarriage

Objective: An understanding of the endometrial receptivity during embryo implantation is essential to avoid recurrent spontaneous miscarriage (RSM). Expression of endometrial receptivity markers including α_vβ₃ integrin and Leukemia Inhibitory Factor (LIF) and pinopodes in women with RSM is explored. Design: Endometrial tissue samples were collected from 16 women with idiopathic RSM (age<;60;35 years) during the mid-secretory phase (D21) of the menstrual cycle from the Institute of Reproductive Medicine, Salt lake, Kolkata, West Bengal, India. 12 normal women having partners with male factor infertility were taken as controls. Only those women who did not receive any kind of medication and had no known causes of miscarriage or other gynecological disorders were included in this study. Materials and Methods: The collected tissue was divided into three parts: one part was used for stromal and epithelial cells isolation for flow cytometric analysis of the biochemical markers, the other part was fixed for immunohistological staining. The third part was also fixed and examined for pinopodes using SEM. Data were compared using independent two sample `t´ test and chi-square test, as applicable. Statistical significance was defined as p ≤0.05. Results: Expression of α_vβ₃ integrin, LIF and pinopodes were observed to be significantly less, both in stromal and epithelial cells of the endometrium in women with RSM when compared with controls. Conclusions: Poor expression of the molecular mediators, α_vβ₃ integrin and LIF in women with RSM correlates well with poor endometrial receptivity. In view of the fact that pinopodes are essential for successful embryo implantation, it is suggested that morphologically abnormal pinopodes in RSM is possibly one of the main causes adversely affecting implantation of the embryo.