What is the endometrial receptivity test?
The Endometrial Receptivity Test is a genetic analysis of a sample of endometrial tissue to determine the ideal time to transfer the embryo into the uterus as part of the IVF procedure.
How does this test help me?
The Endometrial Receptivity Test or ERTest is useful – for increasing the likelihood of success of in vitro fertilization procedures.
Changing the time window of endometrial receptivity can be a cause of infertility in women who have had two or more failed embryo transfers after IVF.
Thanks to this analysis, adjustments can be made to tailor the fertilization procedure and plan the embryo transfer at the time when the endometrium is receptive for successful embryo implantation.
For example, if a post-receptive result is obtained, the optimal day for embryo transfer would be before the classically calculated day, and in the hormone replacement cycle, it would mean day 4 after the first dose of progesterone instead of day 5.
ERTest analyses the expression of 300 genes related to endometrial receptivity as well as the immune response associated with implantation. It is therefore more sensitive than the classical method of dating endometrial status based on histological criteria, which are highly subjective.
For whom is the endometrial receptivity test recommended?
Endometrial receptivity testing is intended for patients undergoing assisted reproduction treatments, especially those who have had several failed IVF attempts due to implantation problems.
It is therefore particularly recommended for patients who have had two or more unsuccessful IVF cycles, irrespective of the use of good quality embryos with good morphologies and normal chromosomes (PGT-A).
Recent studies show that ERTest has helped improve pregnancy rates by up to 51-63% in patients who have previously experienced recurrent implantation failures.
What are the possible results and how can they be interpreted?
For the endometrial receptivity test to be performed correctly, an endometrial biopsy must be obtained seven days after the endogenous LH peak (LH+7) of a natural cycle or 5.5 days after the first dose of progesterone (P+5.5) in a hormone replacement cycle.
The procedure is simple. Oocytes are collected and fertilized during the first cycle to obtain embryo culture. In the second cycle, an endometrial biopsy is obtained.
It is a quick and easy procedure carried out in a specialist practice. The sample is taken by a gynecologist and sent to the laboratory for processing.
This sample is then analyzed to check the endometrium’s receptivity and estimate the optimal day for embryo transfer. Following this analysis, there are three possible outcomes:
Indicates that the endometrium is not ready to receive the embryo, therefore transfer on that date is not possible.
Indicates that the timing of the biopsy was optimal for embryo transfer.
Indicates that the endometrium has already passed the optimal stage for implantation.