Endometrial Receptivity Array Test (ERA)

What is Endometrial Receptivity Array(ERA) Test?

During an IVF cycle, a doctor does an ultrasound to examine the thickness and pattern of the endometrial lining in preparation for embryo implantation. Though ultrasounds are viable, there are some cases where patients who have an appropriate endometrial lining and transfer of morphologically high-quality embryos, fail to successfully conceive, and have a live birth following an IVF cycle. 

In such cases, the endometrial receptivity array (ERA) attempts to analyze the endometrial lining at the molecular level, and helps the doctor gain more information about the window of implantation by evaluating 248 genes.

How does Endometrial Receptivity Array Help in IVF Treatment?

Conceiving is a very complicated process with many variables involved. A woman first needs to ovulate and once the egg is released, it is viable only for 12-24 hours. The egg then needs to be fertilized and implanted into the uterine lining to develop. For implantation to occur, the uterine lining must be capable of receiving and nurturing an embryo. During each monthly cycle, a woman’s uterine lining is most receptive for a period of 4-5 days known as the ‘window of implantation’.

An ERA biopsy can be used to identify when a woman’s uterine lining is in that window of implantation. An ERA is also a diagnostic tool used to determine if a woman’s uterine lining is a contributing factor in recurrent IVF implantation failure and recurrent pregnancy loss.

When to consider an ERA Test

An ERA biopsy isn’t mandatory for all women undergoing fertility treatments and isn’t a part of standard female fertility evaluations. Also, it is not typically recommended for first-time IVF patients.

An ERA biopsy may be an option for women already undergoing infertility treatment. It is also typically recommended for women who have had previous IVF cycle failures or have experienced miscarriage or recurrent pregnancy loss. A patient must be open and discuss their situation and case history with the doctor for them to be able to make apt recommendations and suggest appropriate treatment options.

Process of ERA test

Typically, an ERA biopsy will be conducted by your doctor a month or more than a month before your frozen embryo transfer. The doctor will recommend for the woman to take estrogen and progesterone medication prior to the procedure to prepare for the frozen embryo transfer. An endometrial biopsy is performed on the standard embryo transfer day (in lieu of an actual embryo transfer) when the window of implantation is expected to occur. The procedure is straightforward and there will be minimal discomfort caused.

During the biopsy the doctor inserts a small instrument called a pipelle through the vagina. The doctor will use the pipelle to “scratch” the uterine lining and obtain a small amount of tissue for testing. Some women experience cramping or light bleeding during or after the procedure. The sample will be sent to a lab where molecular analysis is completed to determine the best time to attempt embryo implantation in a future IVF cycle. 

The doctor will then discuss the results of the test with the patient which may be as follows:

1. Pre-receptive – The lining is not yet ready to receive an embryo, and implantation is less likely to occur.

2. Receptive –  The lining is ready to receive the embryo, which is most likely to implant.

3. Post-receptive –  The lining has already reached the stage for optimal embryo implantation but is no longer in that stage. The embryo is less likely to implant currently.

The doctor will then discuss the next steps and course of action based on the results received. 

Cost of ERA test

As this is a simple and day long procedure, the cost of an ERA biopsy is minimal and ranges between INR 35,000 to 40,000. 

An ERA (Endometrial Receptivity Array) biopsy is not mandatory but may be recommended by your doctor in case of recurrent IVF failures and pregnancy loss.