Endometrial Receptivity Assay(ERA)

The chances of implantation failure during the IVF cycle are hugely reduced by undergoing this genetic testing. In this test, a small sample of the endometrial tissue is collected to evaluate the best time when the uterus is ready to accept the embryo. The main cause of implantation failure such as uterine receptivity issues and genetic abnormalities can also be solved with this advanced technique.

When is it done?

Recurrent Implantation Failure (RIF)

In most of the cases of RIF, it has been detected that the main cause behind it is the improper time of embryo transfer. If the embryo is transferred during the non-receptive stage then the chances of successful implantation are extremely minimal. In such cases, the doctor performs an ERA to determine the ideal time. If the IVF cycle fails even after an ERA then the cause of implantation failure can be considered as genetic factors.

Unsuccessful IVF Cycles

You are also an eligible candidate for an ERA if you experienced unsuccessful IVF cycles. The ERA tests enable the infertility specialist to understand the ideal window time when the rate of successful implantation is higher. A successful implantation is indeed the most vital factor for IVF success. This genetic test can also be used if you’re using frozen embryos.

Limited Number of Embryos

Women with advanced age can also consider undergoing an ERA since as women age the number of quality embryos also decreases. The diminished ovarian reserves make it essential to properly use the embryos for implantation.

Tools Used To Study Endometrial Receptivity

Ultrasound

The endometrial receptivity analysis can be done with the help of an ultrasound. The endometrial ultrasound will help in determining the endometrial volume, thickness, and pattern to understand the receptivity window. This method can also help in understanding uterine contractibility.

Endometrial Genetic Tests

To determine whether the endometrium is ready for implantation or not, certain genetic tests such as microRNA expression and transcriptomics can also be used. This helps in determining the genetic patterns of the endometrial tissues.

Histological Analysis

The histological analysis of the endometrium can be done with endometrial biopsy. This technique helps in determining the accurate cellular structure of the endometrium. The only drawback of this technique is that it is an invasive method.

Procedural Details

• The first step of an ERA process is to collect the samples from the uterine lining. Before taking the sample, the patient is directed to take progesterone supplements for 5 days. This is the main hormone which is responsible for making the embryo receptive.
• After collecting the sample, the expression of the genes will be analysed to determine whether the endometrial lining has properly developed to accept the embryo or not.
• The next step of an ERA process is to conduct an endometrial biopsy where a thin catheter will be inserted into the uterine cavity via the cervix. A small tissue will then be collected with a plunger.
• The collected samples are then sent to the laboratory for analysis of the 236 genes. This understanding helps in getting a deeper insight into the endometrial receptivity phases.

Potential Results

The ERA test divides the overall menstrual cycle into 5 phases, which include:

• Pre-receptive: This is considered the time before the implantation window
• Early receptive: This time indicates that the endometrium is near the ideal implantation window
• Receptive: This is the ideal implantation window time
• Late receptive: This is the time when the implantation window is closing
• Post receptive: The implantation window is closed in this stage

Benefits

An ERA is a highly effective test procedure that has a wide range of benefits. The main benefit of this test is the higher chances of pregnancy success. Some of the other benefits include:

• Improved Patient Satisfaction
• Personalized Treatment
• Ideal Time of Embryo Transfer
• Minimal Chances of Implantation Failure