Tests that analyze gene activity in the uterine lining to estimate whether it is in the “window of implantation,” when an embryo is most likely to implant.
They are usually done during a mock (test) cycle: the uterus is prepared as if for an embryo transfer, but instead of transferring an embryo, a small endometrial biopsy is taken. The sample is analyzed for a gene expression pattern associated with receptivity. If the lining is labeled “non-receptive,” the timing of a future transfer may be adjusted earlier or later to better synchronize the embryo and uterus.
Common examples include the ERA, rsERT, ERPeak/ERMap, and WIN-Test.
Synonyms:
ERA, Endometrial receptivity array