When you’ve been trying to conceive for a while and you turn to the in vitro fertilization process to help build your family, you want to make every effort to have the best possible outcome. While IVF is known to have high success rates, knowing the ideal time to transfer your embryo can be incredibly helpful. This is especially true if you’ve had a history of 2 or more unsuccessful embryo transfers. If the embryos you’re transferring are good quality (whether they are your own or you are using donor eggs or donor embryos), but they haven’t implanted, the ERA test can be worth speaking to your doctor about to see if it’s something he or she would recommend. What is an Endometrium? The endometrium is the tissue that lines the uterus, and it typically thickens in anticipation for an embryo to implant during your menstrual cycle. If the egg is not fertilized or if an embryo does not implant, the uterine lining sheds itself, which is when a woman gets her period. Before the ERA test was developed, your doctor could only observe your endometrial lining with an ultrasound. While this is helpful in measuring how thick or thin your lining is, the ERA test can help provide additional insight into both the environment and quality of your endometrium. This information can be invaluable when it comes to IVF. What is Endometrial Receptivity? According to Carlos Simon, a clinical researcher and Gynaecologist who was a part of the research that helped develop the ERA Test, taking into consideration the timing between the development of an embryo and the status of the endometrial lining can be key in achieving a pregnancy. Endometrial Receptivity is the stage in which Endometrium is prepared to allow the embryo’s implantation, this stage occurs in a limited time fragment named “Window of Implantation”. ERA testing bases endometrial receptivity on several factors that includes 248 genes. This helps determine your best window of implantation. What’s important to realize is your window can differ from someone else’s. Having this additional intel can assist your doctor so that he or she can personalize your care and IVF protocol. This means your embryo transfer would be scheduled and tailored around exactly when your endometrial receptivity is at its most optimal for implantation. What Exactly is the ERA Test? Now that you know what your endometrium lining and endometrial receptivity are, let’s discuss exactly what an ERA Test is. During your fertility journey, you may have heard terms such as “ERA Biopsy”, “ERA Testing” or just “ERA”, but you may not have heard what these three letters stand for or how they can help you. ERA is short for Endometrial Receptivity Analysis. It is a genetic test performed on a very small sample of a woman’s endometrial lining to determine which day would be the best day to transfer the embryo during an IVF cycle. The sample taken is also referred to as an ERA biopsy and the whole procedure in general is called either an ERA Test or ERA Testing. Who Should Consider the ERA Test? The ERA test is something best discussed with your doctor to determine if it’s right for you and your diagnosis or fertility history. Some factors worth considering are: Patients who have had 2 or more unsuccessful embryo transfers Patients who have had concerns with endometrial lining (example: thin endometrial lining) Patients who have had had unsuccessful implantation with high quality embryos In general, any patient who has gone through an IVF treatment could be favored by her endometrial diagnosis previous to receiving her embryos The ERA test has been found to improve global pregnancy rates up to 73% in the personalized transfers made according to the test results (Fertility and Sterility, September 2013). Knowing this can be empowering since, as an informed patient, you can take an active part in your fertility care. If you feel that an ERA biopsy might be a fit, speak to your doctor to discuss it. Infertility treatment is always evolving, and your medical team is there to work with you to find what would work best for you to reach your goals!