Effect of Ovarian Induction Using PMSG and HCG hormones on Uterus Dendritic Cells Population in NMRI mice

Introduction: Ovarian hyper-stimulation is widely used in IVF clinics. The main purpose of this method is to stimulate folliculogenesis and increase the number of oocytes in one cycle. Following ovarian hyper-stimulation, hormonal secretion of the ovary, particularly estradiol and progesterone dramatically increases. Immune cells especially dendritic cells have receptors for the estradiol and progesterone and play an important role in appropriate implantation and successful pregnancy. Increase in estradiol and progesterone concentrations following ovarian stimulation can affect the recruitment and frequency of immune cells particularly dendritic cells. Methods: To explore this issue, blood was collected from two groups of pregnant mice (with and without ovarian stimulation) on the seventh day of pregnancy. The amounts of estradiol and progesterone were measured in the sera. The frequency and localization of dendritic cells in spleen and decidua were also investigated by immunohistochemistry. Results: The results of this study showed an increase of progesterone and estradiol concentrations and a decrease of frequency of dendritic cells in hyper-stimulated group compared to the control group. Conclusion: Considering the increase in progesterone and estrogen concentrations after ovarian induction and the presence of receptors for these hormones on dendritic cells, the changes in frequency of dendritic cells could be explained. Regarding the role of dendritic cells in embryo implantation and regulation of maternal immune response, it seems that their changes may decrease the rate of pregnancy success after IVF.