PGT-A, formerly known as PGS, allows us to test the chromosomes of embryos before they are transferred into the uterus. Why is this important? Because at least half, if not more, of the embryos produced in any IVF cycle have a chromosomal abnormality. PGT-A technology insures only chromosomally normal embryos will be transferred. Without the benefit of PGT-A technology, the transfer of a genetically abnormal embryo might result in one of the following outcomes:

  • No pregnancy, and continued cycles with additional embryo transfers until a normal embryo is transferred;
  • Miscarriage of an abnormal embryo with resulting potential complications and delay in trying again;
  • Very rarely, the birth of a baby with significant chromosomal abnormalities.

An embryo that looks great will not necessarily be chromosomally normal. PGT-A gives more detailed information about the viability of an embryo, embryologists have pointed out.

While transferring a PGT-A normal embryo doesn’t guarantee that a woman will get pregnant, (there may be other factors at play, for example endometrial lining issues), there are advantages:

  • Embryo transfer of a PGT-A normal embryo has a higher pregnancy rate compared to transfer of untested embryos.
  • A woman will get pregnant faster: Remember, at least, 50-60% of embryos arechromosomally abnormal.With PGT-A, only chromosomally normal
    embryos will be transferred, avoiding failed embryo transfer, miscarriage and significant delay in trying to get pregnant again.
  • Decision making: There are times when none of the embryos are normal. Although this can be upsetting, PGT-A technology can help avoid further issues by identifying this early, preventing the transfer of abnormal embryos, and allowing better decision making for next steps.

Although PGT-A is available to anyone undergoing IVF, we particularly recommend it to the following patients:

  • Patients with RPL (recurrent pregnancy loss/ miscarriage)
  • Women age 38 and older who will make more than 4 blastocysts
  • Any woman who will make 7 or more blastocysts
  • Two failed IVF cycles
  • Significant male fertility problems.

If you are interested in discussing PGT-A prior to your IVF planning please consider meeting with your physician, or contacting Karen Spitzer, TRIO’s PGT-A coordinator: or 416-506-9203. She can give you more information about this technology.