Pre-implantation genetic testing for aneuploidy (PGT-A) is rated "red" (unreliable) by UK fertility regulator HFEA

[Angelica Cheng]

Pre-implantation genetic testing for aneuploidy (PGT-A) | HFEA

Treatment add-on with limited evidence

www.hfea.gov.uk

Red

PGT-A for day five embryos is rated red because there is no evidence from randomised controlled trials (RCTs) to show that it is effective at improving the chances of having a baby for most fertility patients.

PGT-A is known to carry some risks for the embryo:

• Although current PGT-A techniques are mostly very accurate, the test may give the wrong result (it may miss an abnormality or detect one that isn’t there).
• Using PGT-A may mean you have fewer embryos to use in treatment, or for freezing to use in treatment later. If any healthy embryos are erroneously discarded in this process, you may have fewer chances to transfer an embryo which could develop into a healthy baby.
• Removing a cell from the embryo may damage it and prevent it from successfully developing once it’s been transferred to the womb.
• Removing part of the embryo may cause changes in later growth in the womb, which may cause problems in later life.
• In some cases, cells within the same embryo are not chromosomally identical (known as ‘mosaic’), which means that PGT-A may show that the embryo has chromosome abnormalities when in fact it’s capable of producing a normal pregnancy or vice versa. In some clinics, mosaic embryos are considered for transfer, even though they show some chromosomal abnormality.