ERA test (Endometrial Receptivity Assay)
The ERA (Endometrial Receptivity Analysis, or Endometrial Receptivity Test) is used to determine the so-called implantation window - the most convenient time for the transfer of the embryo into the uterine cavity.
Determining the optimal time for the embryo to be implanted in the patient's uterus increases the chances of a successful IVF procedure. The ERA test was developed and patented by IGENOMIX R&D, a company at the forefront of reproductive genetics research.
Endometrial receptivity - why is it important for IVF?
Statistics show that IVF cycle failures in as many as two-thirds of cases are due to the failure of the embryo to implant in the uterine cavity. Difficulties with the embryo implanting in the endometrium (endometrium) are often related to its lack of receptivity.
The structure of the endometrium changes during each phase of the menstrual cycle. In most women, the endometrium is optimally prepared for the reception, and subsequent implantation of the embryo, between the fifth and seventh day after ovulation.
Indications for the ERA test
The exact moment when maximum endometrial receptivity is reached varies from woman to woman, so it is useful to determine this with an ERA test, especially if previous attempts at in vitro fertilisation have failed due to lack of embryo implantation.
Indications for the Endometrial Receptivity Test are also recurrent miscarriages and the patient's age above 35 years.
Why take the ERA test?
The ERA test allows a precise determination of the implantation window and thus contributes to increasing the success rate of single embryo transfer (SET) and the chances of the embryo implanting correctly in the patient's uterus.
Running the ERA test
If the patient is undergoing hormonal stimulation, the ERA test is performed on the fifth day after ovarian puncture, after five days of taking progesterone. In a natural cycle, endometrial sampling takes place approximately seven days after the hormone LH is released into the blood.
Material for analysis is obtained by biopsy of the endometrium. The endometrial biopsy is performed by a doctor in the gynaecologist's office after inserting a speculum. Collection of the mucosal sample takes a few minutes, after which the material is frozen at -20°C and transported to the embryology laboratory at the clinic in Warsaw. From there, the sample is sent to the IGENOMIX laboratory in Spain - this takes place every 5th, 15th and 25th of the month.
Following an endometrial biopsy, a woman may experience spotting, general weakness and mild lower abdominal pain. The patient should consult with the doctor performing the procedure if she is taking painkillers.
How long is the wait for an ERA test result?
The waiting time for the result does not exceed twenty days and the results are sent electronically to the laboratory ordering the test. The result is used by the doctor to set a precise date for the transfer of the embryo into the patient's uterus - the day and time when the implantation window occurs.