More Fertility Centers Adopting New Technology To Find The Healthiest Embryo

Source: The New York Times – July 12, 2014

Fertility centers are using new techniques to determine embryo health of an embryo before transfer into the uterus during IVF. Two of these screening tools, pre-implantation genetic screening (PGS) and time-lapse imaging, are routinely used at RADfertility.

Many failed IVF cycles and early pregnancy losses can be attributed to unknowingly transfer embryos with chromosomal abnormalities. However, chromosomal abnormalities can’t be observed during embryo culture in the laboratory. PGS is a tool used to identify whether an embryo has a full complement of 46 chromosomes prior to transfer.

RADfertility uses time-lapse imaging in the EmbryoScope®, a combination incubator, microscope and time-lapse camera. The EmbryoScope® takes images every 10 – 15 minutes, giving embryologists the full picture of an embryo’s development, rather than just snapshots at key points.

Both PGS and EmbryoScope® time-lapse imaging are tools to help RADfertility achieve high pregnancy rates with single embryo transfer (SET). However, some critics note there is insufficient published data to recommend either technique.

Our philosophy at RADfertility aligns very closely with our colleague Dr. Richard Scott at RMA-NJ, who is featured in this New York Times article. We believe every patient with infertility should be able to pursue IVF along with technologies such as PGS and EmbryoScope® culture, with single embryo transfer (SET) as the only acceptable standard of care.

There is a strong argument in choosing PGS for an IVF cycle. The transfer of a normal-appearing blastocyst that also tested normal using PGS has a very predictable rate of normal implantation—50% to 60%—in women of all ages, with a miscarriage rate of less than 10%.

Although all women can produce embryos with chromosomal problems, abnormalities increase with maternal age. Therefore, PGS’s benefits are most pronounced when maternal age is 33 or older. A younger woman benefits if fertility factors such as guarded ovarian reserve and/or a prior history of pregnancy loss are present.

The best chance for achieving a successful and healthy pregnancy is with SET. The increased chance of achieving pregnancy when two or more embryos are transferred is minimal and not justified as acceptable IVF care. Twin pregnancies cause both maternal and fetal health problems and significantly increased short-term and long-term health care costs.

A major concern for couples interested in PGS is cost. With PGS, we can usually achieve a healthy pregnancy quicker than IVF alone, while also avoiding a failed embryo transfer or miscarriage. Repeated transfer costs are not only expensive; the emotional cost of a failed transfer or pregnancy loss is immeasurable.

At RADfertility, we offer two packages to address PGS’s cost barrier. Patients can opt for PGS right away, or defer testing until the future, if it becomes necessary. This second approach is called, “Biopsy and Hold,” but RADfertility will be introducing a more patient-friendly program called TinyTEST (TEST = TrophEctoderm Storage) in the near future. TinyTEST will defer half the expense of PGS testing until actually needed.

PGS has limitations. Because only two to three cells are biopsied and tested from a blastocyst that typically contains 150 to 200 cells, those cells may not truly tell us the actual chromosome status of the entire embryo. This limitation is due to a biological phenomenon known as mosaicism, when cells from different regions of a developing embryo might not have the same chromosomal make-up.

At this time, we do not know the true rate of mosaicism within human blastocysts, and it is difficult to determine the false positive and negative rates from PGS. Researchers are working to estimate the mosaicism rate, and EmbryoScope® data might help us better identify mosaic embryos.

At RADfertility, we believe combining PGS and EmbryoScope® morphokinetic data will help optimize embryo selection. We are currently collecting and analyzing data from our patients who have opted for both PGS and EmbryoScope® culture. It is possible a subset of embryos with normal chromosomes and excellent EmbryoScope® developmental landmarks will successfully implant 70% to 80% of the time, or greater. Stay tuned!