PGD-FISH possible outcomes
No embryo transfer
Not all embryos may be suitable for biopsy. They may however, be suitable for freezing or transfer.
An answer is achieved from over 94% of all embryos tested. For technical reasons, we may not get an answer on an individual embryo and the genetic status of that embryo will be unknown. These embryos may still be suitable for clinical use.
No embryos with desired genetics
Embryos tested and deemed abnormal or affected are unsuitable for transfer.
Hybridization Efficiency: The fluorescent probes need to find matching regions on each chromosome to stick to. Occasionally, the probe does not bind selectively to its target or cannot reach the target to hybridise. This can result in seeing too many or too few chromosomes in a nucleus.
Not every cell in an embryo may contain the same number of chromosomes – this is called mosaicism.
PGD cannot look at every cell in an embryo. Therefore, the biopsy piece may not truly represent the rest of the embryo.