ERA TEST DIAGNOSTIC METHOD

Personalized embryo transfer

1. What is the ERA test?

The ERA test for the endometrial implantation window is an innovative diagnostic method developed and patented by IGENOMIX R&D after more than 10 years of research. This technique allows the evaluation of endometrial receptivity from a molecular point of view.

The ERA test for the endometrial implantation window is an innovative diagnostic method developed and patented by IGENOMIX R&D after more than 10 years of research. This technique allows the evaluation of endometrial receptivity from a molecular point of view.

Сега, по време на процеса на лечение на безплодна двойка, ERA тестът дава  оценка на ендометриума на молекулярно ниво и представлява персонализиран генетичен тест за оценка на състоянието на ендометриалната възприемчивост в имплантационния прозорец. Дали ендометриумът е рецептивен или не, се определя след анализ на експресията на група гени. Ендометриалната биопсия трябва да се извърши в ден P+5 (5 дни след започване приема на прогестерон при цикъл с хормонзаместваща терапия) или в ден LH+7 (7 дни след пика на лутеинизиращия хормон при спонтанен цикъл). След като пробата бъде доставена, се анализира експресията на 238 гени. РНК от пробата с ендометриална тъкан се хибридизира с проби от тези гени. След хибридизация компютърният анализ класифицира пробата като рецептивна или нерецептивна според специфичната генна експресия.

2.Why is an ERA test done?

Over 10 years of research and 3,000 clinical trials support this diagnostic method. The ERA test is used to assess the state of the endometrium and determine whether or not a patient's endometrium is receptive according to the genetic profile at the time the biopsy is performed.

The analysis reveals the timing of the implantation window and leads to personalized embryo transfer (PET) and synchronization based on the individually obtained results.

The test result determines whether or not a woman's endometrium is receptive on the particular day and type of cycle in which the biopsy is performed. If she is receptive, this means that the implantation window is on the day the biopsy is performed, and therefore the blastocyst can implant on that day in this type of cycle.

If non-receptive, the result may indicate a displaced implantation window. Therefore, a second biopsy will be required to determine this shift. According to the first result obtained, a specific day will be suggested for the second biopsy. This gives a greater opportunity to carry out implantation in the next cycle, through personalized embryo transfer (PET).

3. In what cases is the ERA test used?

The ERA test can determine whether a patient needs to customize the implantation window before starting treatment. This diagnostic method has been tested in patients who have failed to implant embryos with good morphological characteristics and quality (at least three embryos in younger women or two in patients over 37). This test is recommended for women with normal parameters of the uterus and with a normal thickness of the endometrium (≤6mm), as well as the absence of reasons for infertility found during the examination. Displacement of the implantation window is found in about 20% of these patients.

4. What are the advantages of the test?

As a diagnostic method to determine the receptivity of the endometrium, the ERA test determines the window of implantation personalized for each individual patient before starting in vitro treatment.

The ERA test shows high sensitivity and specificity in determining gene expression profiles associated with receptivity.

The classic method for determining the state of the endometrium is based on histological criteria. This previous diagnostic technique has been shown not to differentiate between fertile and infertile patients and is associated with a high degree of subjectivity, meaning that these results cannot be applied in clinical practice. The ERA test provides a solution to these problems.

5.Frequently Asked Questions:

• At what cycle can the ERA test be performed?
  The ERA test should be performed in either a stimulated or spontaneous cycle. The diagnosis of endometrial receptivity is valid only for the type of cycle in which the test is performed. Embryo transfer should therefore be performed in the same cycle type for which a positive receptivity result was obtained.

• How is an endometrial biopsy taken?
  A biopsy of the uterine fundus is performed according to a standard procedure with a PipeIle catheter or similar. A sample of about 30 mg of tissue is sufficient (approximately the size of a cube with a side of 3 millimeters).

• How is it determined when to do the biopsy?
  Stimulated cycle: When starting a stimulated cycle, the biopsy is taken after five full days of progesterone (about 120 hours). The day of the first dose of progesterone is considered day P+0, and the biopsy is done on day P+5.
  Spontaneous cycle: The biopsy is taken 7 days after the LH (luteinizing hormone) peak. The day of the LH peak is considered LH+0, the biopsy is done on day LH +7 (after about 168 hours). If ovulation is determined by ultrasound, the day of ovulation is taken as day Ov+0, then the biopsy is done six days later (approximately 144 hours) on Ov+6.

• How is it determined when ovulation is in a spontaneous cycle?
  Времето на овулация в спонтанните цикли може да бъде определено с помощта на тест ленти за LH (лутеинизиращ хормон) в урината, чрез директно измерване на LH в кръвния серум или чрез наблюдение разкъсването на фоликула при  ехографско изследване.

• What actions are taken according to the result obtained?
  Result: "receptive"
  If the patient has frozen embryos or has fresh donor embryos, they can be transferred in a cycle of the same type (stimulated or natural) for which a receptivity result was obtained. If blastocysts are to be transferred in a subsequent cycle, this is done on the same ordinal day on which the biopsy was performed in the previous cycle. If day 3 embryos are to be transferred, this should be done two days before the biopsy from the previous cycle.
  If the patient does not have frozen eggs or embryos and wants to use her own eggs, one cycle of ovarian stimulation should be performed to cryopreserve eggs or embryos. Embryo transfer is performed in a subsequent cycle of the same type (stimulated or spontaneous) for which an ERA test receptivity result is obtained.Result: "Non-receptive" (with recommendation for a new implantation window)
  Ако резултатът от първия ERA тест не е положителен и анализът на генетичния профил показва, че може имплантационния прозорец да е изместен, е необходимо това изместване да се потвърди с втори ERA тест. Този втори анализ ще определи деня, в който ендометриумът е рецептивен и поради това,  размразяването на ембриони и техният трансфер трябва да бъдат планирани спрямо този резултат.Result: "Non-receptive" (no recommendation for a new implantation window)
  If the result of the first ERA test is not positive and the genetic profile analysis does not suggest a shifted implantation window, unfortunately, no therapeutic approach can be offered. This happens in less than 1% of patients.