Effect of exogenous gonadotropins on endometrial maturation in oocyte donors

Asian ethnicity in anonymous oocyte donors is associated with increased estradiol levels but comparable recipient pregnancy rates compared with Caucasians

“…It has been suggested that excessive estrogen exposure might lead to insufficient secretory transformation of the endometrium with dysynchronous glandular and stromal development at the time of expected endometrial receptivity (13)(14)(15)(16). Indeed, several reports have indicated that elevated estrogen levels in autologous oocyte IVF cycles may decrease IVF success (17)(18)(19)(20).…”

Why we should transfer frozen instead of fresh embryos: the translational rationale

“…In animal models, superovulation has been shown to affect the depth of the surface epithelium, the number and length of microvilli, and the mitotic activity in the surface epithelium and stromal cells (28, 29). Both human and animal studies have found that superovulation lowers the expression of specific integrins associated with the window of implantation (30, 31). Evidence also suggests that superovulation may affect the timing of the “window of receptivity,” the time period during which the endometrium is receptive to embryo implantation.…”

Effects of ovarian stimulation on endometrial integrin β3 and leukemia inhibitory factor expression in the peri-implantation phase

“…In stimulated cycles from oocyte donors, a reduced glandular integrin expression correlated with a morphological delay in glandular maturation. Furthermore, in endometrium with more advanced glandular development, integrin expression was found to be higher (10,11).…”

“…Ovarian stimulation induced either lower, similar, or higher integrin expression (10)(11)(12)(13). There are limited data on LIF regulation in the endometrium of controlled ovarian hyperstimulation (COH) cycles.…”