100 patients attending kasr El-Aini IVF center preparing for ICSI cycles are randomized into two groups. In the study group, flushing the endometrial cavity with 2ml of clear follicular fluid surrounding mature oocytes through an IUI catheter is done after ovum pick-up While in the control group, no flushing of the endometrial cavity with FF is done. The implantation rates and pregnancy rates in both groups will be assessed.