ERPeak Endometrial Receptivity Test

Identifying your window of implantation


Timing is key for successful embryo transfer

The CooperGenomics ERPeakSM Endometrial Receptivity Test is a genetic test that identifies the best day in your IVF cycle to transfer an embryo.

An embryo is more likely to implant into the uterus during a short time period called the window of implantation (WOI).

Although the timing of this window is predictable for most women, 30% of women, with a recurrent implantation failure (RIF), have a displaced WOI¹ (meaning it occurs slightly earlier or later than expected). This may explain why some embryos fail to implant, despite being of good quality.

Knowing your window of implantation and scheduling an embryo transfer (known as precision embryo transfer) may increase your chances of getting pregnant through IVF.

Learn more about endometrial receptivity testing?

3 in 10 women
with a history of implantation failure have a displaced WOI1

Precision embryo transfer increases the likelihood of pregnancy for women with a displaced WOI2,3

Women with recurrent implantation failure and a displaced WOI had a 46% pregnancy rate with our ERPeak test4

What is the Endometrium?

Understanding your menstrual cycle

The endometrium is the inner lining of the uterus. During your menstrual cycle the endometrium thickens to prepare for a possible pregnancy. If pregnancy doesn’t occur, the endometrium breaks down and the cycle starts again.

A developing embryo implants into the thickened endometrium to receive the oxygen and nutrients it requires to grow. If these endometrial conditions aren’t right, even a good quality embryo may fail to implant.

The ERPeak test can help determine when your personal WOI may be.

What is Endometrial Receptivity Testing?

Your endometrium is at its most receptive during a time period known as the WOI. If you are undergoing IVF, the window of implantation is usually 5 full days after you begin taking progesterone. Your doctor may refer to this as P+5 and will commonly schedule an embryo transfer for this day.

However, for some women the WOI may occur earlier or later, E.g. at P+4 or P+6.

The ERPeak endometrial receptivity test helps determine when your endometrium may be receptive.


Is the ERPeak test right for me?

The ERPeak endometrial receptivity test is recommended if you have experienced two or more implantation failures despite having good quality embryos, during IVF.

Your IVF clinician will determine if ERPeak testing is the right option for you, guide you through the testing process and, help you understand your results.

Studies have shown an improved pregnancy rate in patients with recurrent implantation failure who have un