Endometrial Injury Prior to Controlled Ovarian Stimulation (COH) in Women Undergoing In-vitro Fertilization in Women With Previous IVF Failure.

All women with history of RIF (as defined by ESHRE) and who wish to undertake another assisted conception treatment cycle are invited to participate in the trial. Women will be randomised to two arms; one undergoing endometrial sampling and control. Women in the experimental arm will be subjected to endometrial scrapping with Pipelle biopsy catheter two times; on days 21 and 26 of the cycle prior to the IVF index cycle and after initiation of the GnRHa in the long agonist protocol. Women in the control group will undergo a placebo procedure using the uterine sound on the same days of the cycle like women in the intervention group.