Penn Fertility Care

Early Embryo Viability and Assessment (EEVA)

The NIES study uses the Early Embryo Viability Assessment Test or Eeva™, which analyzes early embryo development and may have the potential to help embryologists and physicians select the best embryo for transfer. Although this technology is still experimental, previous and current scientific publications have described the benefits of using such a test. This test identifies non-invasive markers that would aid a laboratory technician or clinician the ability to identify viable embryos early. However, in order to understand the science behind the test, one must understand how the embryo develops following normal fertilization.

Upon successful fertilization, normal embryos follow precise timings of cell divisions. These timings include:

  • The time from when the first cell division begins to when it ends
  • The time it takes for a 2-cell embryo to turn into a 3-cell embryo, and
  • The time it takes for a 3-cell embryo to turn into a 4-cell embryo

Based on the optimal timings of these precise cell division events, the Eeva™ test has the potential to predict by Day-2 of embryo development which embryo(s) are more likely to become viable blastocysts. By using non-invasive cell tracking and prediction software, the development of each embryo is automatically analyzed against the validated cell division time periods. If the timing and duration of cellular divisions falls within the defined optimal time points, these embryos are given a HIGH prediction of becoming blastocysts. If division timing falls outside of the optimal time range, these embryos are defined as LOW predictors of blastocyst development.

Although the current NIES study at Penn Fertility Care does not use the automated predictive outcome provided by the Eeva™ test to select which embryos to transfer into the patient, this study provides useful information to compare embryo development and implantation potential. Such technology hopes to be able to help infertile couples achieve pregnancy efficiently and safely and may one day be part of the routine care that patients receive.

Early Embryo Viability Assessment - High
The Early Embryo Viability Assessment analyzes early embryo development and may have the potential to help embryologists and physicians select the best embryo for transfer.

Early Embryo Viability Assessment - Low
The Early Embryo Viability Assessment analyzes early embryo development and can help identify those with a low probability of success.