Endometrial Receptivity Array



Endometrial Receptivity Array (ERA) is the diagnostic procedure that may help to determine whether the endometrial cavity is ready for embryo implantation. Endometrium refers to the inner lining of the uterus to which the embryo must attach itself after fertilization. The endometrium plays a key role in the implantation of an embryo during IVF. The ERA test is meant for evaluation of the functioning of the genes that determine the receptivity of the endometrium. There are over 238 genes that must be assessed through the ERA test. It can also help predict the ideal window of implantation for a particular woman. By doing this, IVF specialists can time the implantation to reduce the chance of implantation failure.

IVF is one of the most famous fertility treatments available. Though it does not guarantee conception, most patients are expected to conceive within 3 IVF cycles. However, some women fail to conceive even after 3 cycles of IVF. In such cases, doctors then begin to search for the reasons why the woman has been unable to conceive. The receptivity of the uterus is one of the possible reasons for this. This can be verified with an Endometrial Receptivity Array (ERA) test.

ERA (Endometrial Receptivity Analysis) assesses the optimum time in the endometrial cycle to perform embryo transfer. Thus, ERA can increase the chances of pregnancy by synchronizing an implantation-ready embryo with a receptive endometrium.


ERA is indicated for patients with recurrent graft failure (RIF) because these patients have a higher risk of transplant window displacement. Therefore, this assay may be useful for patients who have had 2 previous failed cycles with their own eggs or 1 previous failed cycle with donor eggs with good quality embryos implanted into the uterine cavity.

In case your affected person requires any intervention for different uterine factors, the ERA test need to be executed after such intervention in order to reproduce as many of the stipulations in which the embryo switch will take place.

In the case of atrophic (< 6 mm) or hypertrophic endometrium (> 12 mm), the ERA can be done if this condition is constant in all endometrial cycles for this patient.


Endometrial Receptivity Array uses Next Generation Sequencing (NGS) technology to analyze the gene expression of 248 genes related to the endometrial receptivity status. The results obtained from this test are based on the expression analysis of these genes with a computational predictor designed and developed by Igenomix. After sequencing the genetic material (RNA)obtained from an endometrial biopsy, it is possible to evaluate if the endometrium is Receptive or Non-receptive at a given moment of the endometrial cycle. This result can be used to give recommendations for personalized embryo transfer in each patient according to the patient’s specific endometrial profile. In a small number of cases (10%), it is necessary to establish the personalized window of implantation by performing a second endometrial biopsy on the specific day designated by the first ERA test.

In order to ensure the reproducibility of the ERA test, the test must be performed by repeating exactly the same conditions that the patient will undergo in subsequent embryo transfer cycles (type of cycle, treatment method, administration route, etc.), and hormone replacement therapy is always used. Therapeutic Cycle (HRT) or Natural Cycle. This test can’t be performed in controlled ovarian stimulation cycles. The first endometrial biopsy is performed 5 days after progesterone administration (P+5) in the HRT cycle or 7 days after the start of hCG (hCG+7) in the natural cycle.


An endometrial biopsy is performed by an IVF specialist in a simulated embryo transfer cycle prior to an IVF or FET cycle. These samples are then analyzed to evaluate endometrial receptivity and determine the optimal date for embryo transfer. The sample will be sent to a laboratory where molecular analysis is performed to determine the best time to attempt embryo transfer in a future transplant cycle. There are three potential results.

  • Pre-receptive: This indicates that the endometrium is not yet ready to accept an embryo, and implantation at this point may not be ideal.
  • Receptive: This means that the time of endometrial biopsy has been accepted as the optimal time for embryo transfer.
  • Post-receptive: This indicates that the endometrium had reached the stage of optimal embryo implantation but has now gone past it.


One of the most common questions patients ask about endometrial receptivity testing and endometrial biopsy is whether it is painful. Endometrial biopsy is an outpatient procedure that does not require admission to a hospital. Some patients have described having either mild discomfort during the process or mild cramping after. Pain relievers can be purchased at the pharmacy to relieve discomfort. Over-the-counter pain relievers should not be taken without first consulting a doctor.


If you are just trying to conceive and have no history of miscarriage and have never had IVF before, it is worth considering the receptivity of your endometrium. When you have an initial fertility evaluation as a patient, the IVF specialist will first check your ovarian reserve and ovarian function. They also usually do an ultrasound to look at the ovaries and uterus and take pictures of the endometrium. Initially, evaluation of endometrial receptivity is not done unless the doctor thinks it is justified.

If you have any concerns or would like to discuss this alternative, you should feel free to ask your doctor about the ERA test.

It is indicated for all patients starting assisted reproductive therapy and has the greatest benefit in patients with repeated transplant failures.

Although the endometrial receptivity analysis is indicated for all patients starting assisted reproductive treatments, is highly recommended if you’ve undergone two or more IVF cycles that were not successful, where the embryos were of good quality. If you’ve got had miscarriages or more, you can need to invite your physician if Pre-implantation Genetic Testing for Aneuploidy (formerly called PGS) is some thing that they suggest, as it could assist boom the probabilities of getting a healthful child and reduce your probabilities of a miscarriage.

For more queries, Call us at +9196507 25386, +91 011 3560 4368.