Preimplantation genetic screening refers to the removal of one or more cells from an in vitro fertilization embryo to test for chromosomal normalcy. PGS screens the embryo for a normal chromosome number. PGS is a method of chromosome disorder screening on IVF embryos.
First, one or two cells are removed from the embryo.
The cells are then evaluated to determine if the inheritance of a problematic gene is present in the embryo.
Once the PGD procedure has been performed and embryos free of genetic problems have been identified, the embryo will be placed back in the uterus, and implantation will be attempted.
Any additional embryos that are free of genetic problems may be frozen for later use, while embryos with the problematic gene are destroyed.
Trophectoderm Biopsy: Trophectoderm biopsy involves removing some cells from the trophectoderm component of an IVF blastocyst embryo. The removed cells can be tested for overall chromosome normality (PGS) , or for a specific gene defect (PGD).
Blastomere Biopsy: Blastomere biopsy is removal of a cell on Day 3 at the “cleavage” stage – before a blastocyst is formed. Day 3 embryo biopsy is traumatic and lowers the embryo’s potential for implantationWe generally choose to do trophectoderm biopsy.
We generally choose to do trophectoderm biopsy.