What is ERA testing in IVF?

If you have had a failed IVF cycle despite good quality embryos and a good transfer process at the hands of an experienced doctor, you may consider the endometrial receptivity analysis, commonly known as ERA testing in IVF.

ERA test can optimize the chances for successful implantation, especially if there is a concern about your endometrial lining, which is not evident in any of the other tests.

Can ERA testing in IVF improve pregnancy rates?

During your menstrual cycle, there is a short period of time during which your endometrium is in this optimal condition, this is referred to as your ‘implantation window’. The ‘implantation window’ is thought to be around 6-10 days after ovulation.

The ERA test can determine whether this ‘implantation window’ is happening for you at the expected time. Thus, allowing your doctors to better time your embryo transfer.

Evidence (1) shows that 25 percent of recurrent implantation failure patients who undergo the ERA test had a non-receptive lining at the expected implantation time. Embryo transfer at this time is likely to lead to implantation failure, causing IVF failure, and consequent emotional and financial distress.

What is the ERA procedure?

ERA is a genetic test performed on a small sample of a woman’s endometrial lining to determine the best time for embryo transfer in an IVF cycle that will give the highest chances of a successful implantation.

Your genes determine the receptivity of your endometrium as exhibited by the endometrial cells, which produce varying levels of certain kinds of RNA during the more receptive time. ERA evaluates the expression levels of the 236 genes.

Endometrium is labelled as ‘receptive’ or non-receptive’, depending upon the patterns in RNA production.

ERA test is also highly reproducible—on retesting the endometrial samples taken during a particular time in the cycle even after months, the results remain unchanged.

By examining the expression of these genes, the ERA finds your personal window of implantation (which is normally between day 19 and 23 of the period cycle), when the endometrium is most receptive. With ERA, the main goal is to determine the ideal day for embryo implantation to have the highest chances of success.

How is the ERA test performed?

The first step is the biopsy of the uterine lining, which can be simply done in-office, without anesthesia. A plunger attached to a catheter is inserted in the uterine cavity through the cervix, and it uses suction to draw a very small sample of the endometrial tissue.

How painful is ERA biopsy?

It can be done quickly without much discomfort or pain.

How does ERA work?

This endometrial sample is sent to the genetic lab for examination and cells are analyzed to predict if the endometrium is ‘receptive’ or ‘non-receptive’ on the supposed day of embryo transfer. The results of ERA test are available in approximately 3 weeks’ time.

The test is typically done during the ‘mock cycle’ on the day on which embryo transfer would have been done in the actual cycle.

How long after ERA is embryo transfer?

Your FET after ERA test can be done in the next cycle using the same timing, if the endometrium is found to be adequately receptive

If the endometrium is non-receptive, your window of implantation may be displaced and the doctor will adjust Progesterone administration accordingly to create optimal implantation environment.

The ERA test will be performed again to identify the new window of implantation and if correct, the embryo transfer can be done accordingly in the next cycle.

Who needs endometrial receptivity analysis?

For around 80% of women, the window of implantation falls in the standard expected time. This means that 20% or 1 out of 5 women will need a different protocol to determine their unique window of implantation.

The ERA test is useful in finding the optimal time of embryo transfer in women whose window of implantation is altered so that the doctor can adjust the medications accordingly and create their personalized embryo transfer (pET) time, thus giving them the highest chances of a successful pregnancy.

You should consider the ERA test if you have:

• Had unsuccessful implantation, despite good graded embryos
• Had more than two unsuccessful embryo transfers
• Concerns regarding your endometrial lining

Based on your endometrial diagnosis, your fertility specialist may recommend the ERA test during your IVF cycle.

IVF success rates with ERA testing

A study published in the Journal of Human Reproductive Sciences, found that using by undergoing an ERA biopsy 127 out of 175 women (72.6%) were able to have a successful pregnancy with personalized embryo transfer (pET) (2).

Although not recommended in all cases, ERA has been a key intervention for some patients, who were otherwise feeling hopeless due to recurrent IVF failures.

Should I opt for ERA testing in IVF?

A pilot study (3) looking at the effect of ERA testing for patients with previous implantation failure shows that successful implantation can be achieved when the results are used to time embryo transfer effectively.

However, there appears to be little benefit to patients without previous implantation failure having an ERA test.

How much does ERA cost?

The cost of your ERA test really depends upon your location and the clinic standards. ERA prices in different locations are listed below

Get in touch via the red contact button on this page to find doctors that offer ERA testing in IVF.

Reviewd by: Dr. Meenakshi, PhD