Endometrial Receptivity Assay (ERA)
When women fail to conceive from a transferred embryo during in vitro fertilization, the question arises as to whether this could be a problem with the ability of the uterine lining to accept an embryo. More specifically, has the embryo been transferred during the optimal implantation window, a window that is based on the duration, not amount, or progesterone exposure. This is the purpose of the ERA test.
The ERA evaluates over 230 genes from a sample of uterine tissue, which is then fed into a computer to provide a result as to whether the uterus is receptive or non-receptive. In approximately 75% of cases the lining is receptive, and the duration of progesterone is optimal. In the other 25% of cases the lining is NON-receptive and in 2/3s of cases the lining is preceptive meaning that the first dose of progesterone needs to be given earlier, usually 8 to 12 hours earlier.
Unfortunately, there is not universal acceptance as to the utility of the test. This is largely since there has yet to be a large randomized prospective test as to its value in assisting women with repetitive implantation failure.
At Carolina Conceptions the physicians have agreed that women who have repeat implantation failure should receive two weeks of Doxycycline, an antibiotic that would treat an asymptomatic infection or inflammation of the uterine lining with Mycoplasma or Ureaplasma.
The physicians also agree that women should CONSIDER the ERA
- If they have failed to conceive after transferring one euploid
(chromosomally normal) embryo
- If they have not done a transfer but have only one euploid embryo
- If they have failed to conceive after undergoing two consecutive embryo
An embryo transfer after ERA is still only successful in about 60% of cases.