Should ERA testing be routinely performed in recurrent implantation failure?

No. Endometrial receptivity testing should not be performed routinely in recurrent implantation failure. The UK regulator, the HFEA, rates endometrial receptivity testing red on its treatment add-ons scale — meaning there is no evidence it is effective at improving the chance of a live birth. The trial evidence supports that rating. A large randomised controlled trial found no benefit from ERA-guided personalised embryo transfer. A 2022 study reported that ERA-guided transfer following a previously failed transfer was associated with lower cumulative and per-transfer live birth rates than standard timing. The practical position: the test is expensive, requires an additional biopsy and a mock cycle, delays treatment, and the best available evidence does not show benefit — with at least one dataset suggesting harm. Where a patient requests it, the counselling should be explicit about the regulator rating and the trial evidence rather than framing it as an option of uncertain benefit. For recurrent implantation failure, effort is better directed at investigating the uterine cavity by hysteroscopy, excluding and treating chronic endometritis, reviewing embryo quality and laboratory factors, and reassessing the transfer protocol.