Endometrial Receptivity in PCOS
It is generally believed that in most cases polycystic ovary syndrome (PCOS)-related infertility results from the absence of ovulation, yet there is also evidence that anovulation may not be the only reason for these women’s failure to conceive. Among factors that may contribute to subfertility in these subjects, a special role can be attributed to endometrial dysfunction, a phenomenon also characterized by a variety of changes in endometrial histomorphology and receptivity markers, which apparently cannot be corrected by conventional doses of progesterone. A number of investigations have documented the existence in the endometrium of women with PCOS of altered markers of endometrial receptivity during the implantation window. In this respect, the existence of a degree of resistance to the action of progesterone in women with PCOS seems to play a crucial role.