['To assess the impact of single pass outpatient endometrial biopsy in patients at the highest risk for an endometrial cause for failed implantation; those that have failed to conceive despite the transfer of morphologically normal euploid embryos.', "This is a retrospective cohort study consisting of all patients less than 42 years old who failed their first euploid blastocyst transfer and subsequently completed a second transfer cycle of euploid blastocysts. Cycles were analyzed to determine if a single pass endometrial biopsy, termed 'endometrial disruption', was performed in a cycle preceding their second embryo transfer. Transfer outcomes were analyzed and implantation rates calculated. Data analysis was performed to compare outcomes between patients who had endometrial disruption performed versus those that did not.", 'Two hundred ninety patients failed their first euploid embryo transfer and subsequently completed a second euploid embryo transfer and were included. Thirty-nine patients underwent endometrial disruption and 251 did not. There were no statistical differences in clinical implantation rate or sustained implantation rate between the group with endometrial disruption and subjects without any intervention (Clinical IR, 43.6 % vs. 55.0 %, p\u2009=\u20090.13; 38.5 % vs. 42.6 %, p\u2009=\u20090.60). When controlling for transfer order there was no statistical difference noted in implantation rates.'] Does endometrial disruption improve implantation in patients who have failed the transfer of euploid blastocysts?