Intrauterine insemination (IUI) comprises the insertion of a high number of washed and processed spermatozoa directly into the cervix to the uterine cavity around the time of ovulation to increase the chances of pregnancy. It is usually used for couples with mild male factor infertility, unexplained infertility, cervical factors, mild endometriosis, and psychological, sexual dysfunction. The endometrium, which lines the uterus, is prepared for the implantation of the embryo; this process starts in the proliferative phase and extends throughout the luteal phase. Implantation, a crucial phase of pregnancy, is a complicated process, and more than half of failures to achieve pregnancy are caused by implantation failure. To assess the influence of endometrial flushing of 1000IU hCG done prior to IUI procedure on pregnancy rate in infertile females undergoing IUI treatment. The present study was applied to 80 infertile subjected to ovarian stimulation protocol using letrozole and hMG in doses adjusted according to their response; triggering was done using subcutaneous HCG. The results of the present study showed no significant difference regarding initial characteristics, indication for IUI, basal menstrual cycle characteristics, ovarian stimulation characteristics, and semen parameters before and after processing, while there was a significant difference between both groups regarding biochemical and clinical pregnancy rates. In IUI cycles, endometrial human chorionic gonadotropin (hCG) flushing done 5-10 minutes prior to IUI can improve biochemical and clinical pregnancy rates.