How does Endometrial Receptivity Array help IVF patients?

Fertility treatment in India and globally has become very popular. This is due to the fact that many couples are finding it increasingly difficult to conceive naturally. After a year of unprotected regular sex, if a couple is not pregnant, they are clinically termed as infertile. However, some couples keep trying and have been able to conceive the following year or even a few years later without any medical help. But these are rare instances and should not be taken as a possibility that you might be able to conceive naturally at a later stage. A vast majority of couples who were not able to conceive in the first year are not able to conceive later as well.

Some couples consciously plan delayed parenthood. This is a concept that has gained much popularity of late. Couples, where both partners are working, would like to focus on their careers rather than get distracted with having children and family planning at the onset of their marriage. They take comfort in the fact that medical science has advanced enough to allow them to have a baby at a later age. However, late pregnancies come with risks and at a higher cost. Once the female partner crosses 35, and the male partner crosses 40 years, the likelihood of being able to conceive naturally reduces.

The couple who are not able to conceive naturally opt for Assisted Reproductive Techniques (ART) to help them have a baby. IVF is the most successful ART due to its high success rates. Conception is a complicated process, and the factors have to be perfectly aligned for the woman to get pregnant.

There are many advanced Fertility treatments that have helped to identify the weak areas that have been hindering some IVF patients from conceiving. With the help of these advanced techniques, many couples have been able to have a baby successfully.


In vitro fertilisation literally means fertilisation in a glass dish. This is a process in which the egg and the sperm are fertilised in a laboratory under the supervision of an embryologist. The ovaries are stimulated with hormone injections to enable them to mature a larger number of eggs than they normally would for a cycle. The female eggs are extracted directly from the ovaries through an egg retrieval procedure. The process of collecting the male sperm is much simpler, and the male partner is given a sample cup in which he has to ejaculate after masturbation.

Once the eggs and the sperm are both available in the lab, each egg is put in a dish with approximately 10,000 sperm for fertilisation. The eggs that fertilise form embryos. When the embryos are a few days old, they are transferred to the uterus. Some doctors transfer the embryos when they are 3 days old, and some doctors culture the embryo for 5 or 6 days when they become blastocysts.

The most crucial part of the IVF treatment is the period after the IVF transfer. This is when implantation has to take place. The embryo that was transferred to the uterus has to attach itself to the endometrial lining. Once the embryo has implanted itself to the endometrial lining, it will receive nourishment from the mother and grow into a baby. The tissue lining on the inner wall of the uterus is called the endometrium. As the uterus prepares for the embryo, oestrogen is released by the body, which causes the endometrium to get thicker. At optimum thickness, it is receptive for the embryo and implantation can take place easily.


Sometimes the embryo does not attach itself to the endometrial lining. This embryo then disintegrates and is then expelled when the next endometrial lining is shed. Women may experience a slightly heavier period flow.

The big question here is – why didn’t the embryo implant? What went wrong? There are a number of reasons due to which the IVF procedure can fail. The most common causes of IVF failure have been identified as
– Weak embryo
– Unreceptive endometrial lining

There are other causes as well, but a large percentage of IVF failures are due to these two reasons. There are some options to deal with weak embryos such as transferring more than one embryo to ensure that at least one will implant successfully. The only way to check if the uterus is receptive is through an Endometrial Receptivity Array (ERA) test. The receptivity of the endometrium is important for implantation to take place.


A uterus is considered receptive when it is ready to receive the embryo. It has been assumed that the uterus is usually receptive between the 19th and the 21st day of the menstrual cycle. The receptivity period is known as the “window of implantation”. This is when the endometrium will easily accept the embryo that comes into contact with it.

Every woman has a different cycle, and the receptivity of the uterus varies. Therefore not all women will have an optimal receptive uterus at the same time. This means that for the doctors to transfer the embryo to the uterus at the right time, they need to know exactly when the endometrium is at its peak receptivity.

A 3-day embryo transfer is usually performed around the 17th day of the menstrual cycle. This means the embryo has to wait two days for the uterus actually to accept it. The blastocyst if transferred as a 5-day culture, will make it in time on the 19th day of the cycle. However, a blastocyst that is transferred as a 7-day culture might just miss the implantation window. Being aware of when exactly the uterus is most receptive is very helpful for doctors. This enables them to transfer the embryo during the fertility window, which results in successful implantation.

When the embryo transfer and the endometrial receptivity is not synchronised, it could lead to implantation failure. If the embryo is placed in the womb in either a pre receptivity state or a post receptivity state, the probability of implantation is minimal. Transferring the embryo either prior to the implantation window or after the implantation window will result in implantation failure.


To check when the endometrium is receptive, a woman undergoes an endometrial biopsy. This biopsy is taken on a particular day of the menstrual cycle. This test involves the sequencing of 238 genes from the retrieved endometrium tissue. The endometrial receptivity analysis is known as a personalised genetic test which stats whether the endometrium is receptive or not receptive. The gene ex.pression helps to ascertain the state of the endometrium and when it will be receptive. Based on this, the window of implantation is calculated.

Taking the biopsy is a quick and easy process which can be done in the consultation room itself. This tissue sample is then analysed, and a personalised Endometrial Receptivity Array is prepared. The array gives a detailed reporting of the pre-receptivity, receptivity and post-receptivity state of the endometrium.

Pre-receptivity: The uterus is not receptive as yet and will take a while. An embryo placed in the uterus in the pre-receptive stage will have to wait for the endometrium to be receptive. Sometimes the embryos arrest before they can implant.
Post receptivity: This is the stage after the uterus has crossed its optimal receptivity, and the receptivity level of the endometrium is reducing. If the embryo has been placed in the uterus post receptivity, the embryo is not going to implant. Invariably soon afterwards you will have your periods.


The Endometrial Receptivity Array test is not recommended for everyone. Doctors usually recommend ERA for patients who have had more than 2 IVF cycle failures and are over the age of 37. Patients whose IVF cycles have failed with good embryos are also recommended the ERA test. Sometimes the embryo is transferred post-receptivity, and this causes the implantation to fail even though the embryo is good. In these cases, it is important to know when the endometrium is at optimum receptivity.

The ERA test comes at an extra charge and helps to determine the endometrial receptivity for subsequent IVF cycles. It is done by analysing the gene ex.pression of the endometrium. Usually, the ERA test results take around 3 weeks to come. If a doctor suspects that the IVF cycle is failing due to poor receptivity or non-receptivity of the uterus, they may recommend an ERA in the cycle prior to IVF transfer. It is better to delay the embryo transfer by a month than end up with another failed implantation.

Doctors also prefer to conduct the IVF transfer with frozen embryo rather than culturing fresh embryos in the lab until the endometrium is receptive. They do not recommend keeping the embryo in the lab beyond 7 days. Hence if the endometrium receptivity is delayed, the frozen embryos are preferred.

A displaced implantation window is found in a large number of patients. Statistics revealed that about 25% of the women who have had the ERA test have a displaced implantation window. In these cases, the doctor performs a personalised embryo transfer (pET).

Naveen and Anuradha were very frustrated with their IVF treatment failing each time. They were both young and healthy. Anuradha suffered from damaged fallopian tubes due to a surgery which as brutally performed. IVF was the only option for them. Tests revealed that her uterus was healthy, and due to their young ages, their eggs and sperm were assumed to be healthy as well. Anuradha had a normal menstrual cycle and no problems with her hormones. When they came to Medicover Fertility, the doctor recommended an ERA based on her medical history. The test results showed that in previous cycles, the embryo transfer was being conducted on a wrong day, and hence the IVF cycles were failing. She had an unusual case of a slightly earlier receptive uterus, which began declining by the time the embryos were transferred. At Medicover, the embryo transfer was conducted with frozen embryos based on the endometrial receptivity array, and she finally had successful implantation, which led to a healthy pregnancy and beautiful baby.


There have been many implantation failures due to the unreceptivity of the endometrium. Now that doctors can check exactly when the endometrial lining is ready to receive the embryo, the IVF transfer can be performed accordingly. The Endometrial Receptivity Analysis has benefited the IVF industry multi-fold. The ERA test has been found to be very accurate in determining the implantation window as compared to all other methods used previously.

Save time: A lot of time was wasted between IVF cycles each time the procedure failed, and the next cycle was started. With the ERA, couples no longer have to wait and hope for a baby. The ERA improves the probability of having a baby during the next cycle. It does away with the time lag of months or even years.

Fewer IVF failures: The ERA test determines when the endometrium is most receptive to receive the embryo and hence, the number of IVF cycles are reduced, and the probability of implantation is increased.

Successful pregnancy: Every couple looks forward to a successful pregnancy. The news of implantation failure is devastating. Being able to detect the receptivity of the uterine lining enables the doctors to transfer the embryo during the implantation window when it is sure to the implant. This precise timing increases the chances of a successful pregnancy.

Save money: Irrespective of how much money you have, IVF treatment is not cheap. Repeated IVF cycles are not only emotionally taxing and physically draining but can be financially depleting as well. The improved chances of IVF implantation success with ERA help couples to save money by preventing them from having to spend for further IVF cycles.

Their benefits of ERA all revolve around ending up with successful implantation since the doctors know the right time to conduct the procedure.


The nagging thought concerning risks always plays on the back of the mind. The Endometrial Receptivity Analysis is a very simple procedure. The process of taking the biopsy is similar to a pap smear and can even be done in a consultation room. There are no known risks associated with giving the biopsy for the ERA.

The procedure is not painful. A catheter-like device is inserted through the cervix into the uterus to obtain a tissue sample. Most women find the process very uncomfortable and invasive. However, the good news is that it just takes a few minutes to get a biopsy.


Medicover Fertility has always believed in giving their patients the best service. This includes incorporating the latest techniques and treatments that will help patients achieve better success in IVF treatment.

Many patients come to Medicover Fertility after experiencing several IVF failures at other fertility hospitals. Here patients come with hope and expectancy that Medicover will do something revolutionary and give them instant success. To some extent, this is true, and with the help of advanced fertility techniques, Medicover has been able to uphold these starry-eyed expectations of patients. Implantation failure has been a common reason why some of the IVF treatments have failed. By testing the receptivity of the endometrial lining and calculating the fertility window, Medicover is able to improve embryo implantation success. This results in pregnancy success.

The focus at Medicover is to understand the condition of infertility that is affecting the couple and provide the fertility treatment accordingly. The couple may have to go through a series of different tests to establish the exact cause of infertility, but in the long run, this helps the doctor to do a more specific treatment that will result in a successful pregnancy.

Medicover Fertility aims at providing high-quality treatment using the latest treatment facilities and advanced fertility techniques. The focus is to work towards a successful IVF treatment.


Q: I have had 4 IVF cycle failures will ERA help me to have a successful IVF?

A: It depends on what was the cause of your IVF failure. If the implantation failure was due to the non-receptive endometrial lining, then ERA will definitely help you have a successful IVF. Check with your doctor regarding having an ERA.

Q: My periods have a time frame of their own and hence the doctors were never sure of when to transfer the embryos. Will ERA help me?

A: ERA follows a pattern approach. If your periods are haywire, endometrial receptivity array may not help you as the implantation window may vary the following month.

Q: What is implantation window? How can I know when my implantation window is?

A: Implantation window is the time frame when the endometrium is most receptive. The implantation window is determined by having an ERA test which involves an endometrium biopsy on a specific day of your cycle.

Q: The doctors said that my IVF failed due to non-receptive uterus, will ERA help me?

A: ERA will help to determine when your uterus is most receptive. It allows the doctors to transfer the embryo accordingly on the receptive day, which in turn improves the chances of implantation.