PGT-A (Preimplantation Genetic
Testing for Aneuploidy)

PGT-A is a very early method of screening that involves checking the number of chromosomes of embryos for any abnormalities. PGT-A enables the selection of the ‘normal or Euploid’ embryo(s) for transfer giving the woman a much higher chance of achieving a pregnancy and livebirth.  With age the probability of having a ‘euploid’ embryo for transfer decreases. Next Generation Sequencing (NGS) is used in PGT-A screening as it is one of the most technologically advanced means of genetic testing.

Who is it recommended for?

Older women are more likely to have eggs with abnormal chromosomes, so this screening is typically offered to women over 38 years of age. Similarly, women who have faced repeated miscarriages or implantation failure may use this test to aid the transfer of a chromosomally normal embryo giving a higher chance of a healthy livebirth.

How does it work?

For us to carry out PGT-A you will have to go through routine IVF procedures so that we can generate several viable eggs for collection. The eggs will then be fertilized in the lab and grown for 5-6 days. Only the embryos which have developed to blastocyst stage are screened and a small biopsy of cells taken. Your biopsied embryos will then be frozen in our onsite laboratory using vitrification whilst we await the results from the specialist genetics laboratory. Only embryos without any chromosomal abnormalities will be placed back in the womb via a procedure called Frozen Embryo Transfer.

Risks and side effects

This risks are similar to those outcomes of a traditional IVF cycle, including multiple births, ectopic pregnancies and miscarriage. Additionally, there may be situations whereby all the embryos biopsied may be chromosomally abnormal. It is also important to bear in mind that not all biopsied embryos will generate a result from the screening test.  Typically 90% of biopsied embryos give a result. Embryos will be classified into two categories post screening: Euploid and Aneuploid.

Disclaimer to HFEA

The above procedure is considered to be a treatment add-on by the HFEA. More information can be found at https://www.hfea.gov.uk/treatments/treatment-add-ons/