Endometrial Receptivity Array
ERA stands for Endometrial Receptivity Analysis. It is a diagnostic test used in reproductive medicine to assess the receptivity of the endometrium (the lining of the uterus) for embryo implantation. The ERA test aims to determine the optimal timing for embryo transfer during an IVF cycle.
The endometrium undergoes a series of changes during the menstrual cycle to become receptive to an embryo for implantation. This receptive window, also known as the window of implantation, is a limited period when the endometrium is most favorable for successful embryo attachment and implantation.
The ERA test involves taking a small biopsy of the endometrial lining during a specific phase of the menstrual cycle, usually during the mid-luteal phase (around 7 to 9 days after ovulation). The collected endometrial sample is then analyzed to assess the expression of specific genes and molecular markers associated with endometrial receptivity.
Based on the analysis of the gene expression profile, the test categorizes the endometrium as pre-receptive, receptive, or post-receptive. This information helps fertility specialists determine the precise timing for embryo transfer that is most likely to result in successful implantation.
However, in the past few years numerous independent groups have published their studies indicating that it is not as promising as it sounds.
Cozollina in 2022 published a multicentric trail where they concluded that Using ERA to guide pET during either autologous or donor cycles after a failed transfer attempt did not improve reproductive outcomes. Conversely, worse outcomes were detected when ERA was used. https://pubmed.ncbi.nlm.nih.gov/36070983/
Rafael et in 2021 stated that Without a gold standard to compare, the claim that the window of implantation (WOI) might be off by ±12 h only requires a good argument for the advantage it provides to human procreation, knowing that embryos can linger for days before actual embedding starts and that the window is actually a few days. The intra-patient variations in the test need to be addressed. In summary, like all other add-ons, it is doubtful whether the ERA test use can significantly enhance implantation success rates.
IVF in most countries including India is self paid by the couple. We strongly feel that any technology should not be offered till we are very certain that it is beneficial beyond doubt. Till then, it is wiser to invest in repeated IVF cycles rather than tests with uncertain benefits.