Preimplantation Genetic Testing
As many as 65% of all embryos created do not survive the first months of pregnancy. Many of these embryos are unable to successfully implant due to chromosomal abnormalities or other genetic conditions.
In our clinic we offer preimplantation genetic testing(PGDand PGS). Preimplantion genetic testing during IVF at the stage of blastocyst allows us to identify the chromosomal or genetic defects to an embryo prior to embryo transfer. The chromosomally normal embryos that we select are high quality and they have the best chance of implanting successfully.
Preimplantation genetic diagnosis
PGD can be performed during an IVF cycle and tests for particular gene defects that are known to cause specific diseases or genetic disorders.These are disorders that one of the parents or both known to carry and which could be passed down to the child.Such examples are sickle cell anemia and cystic fibrosis.
Candidates for PGD
1) Carriers of sex linked genetic disorders
2) Carriers of single gene disorders
3) Those with chromosomal disorders
Preimplantation genetic screening(PGS)
PGS tests embryos for abnormalities in chromosome count(aneuploidy). Chromosomal abnormalities can lead to miscarriage or conditions such as Downs syndrome. With PGS couples have greater chances of a successful IVF and birth of a healthy baby.
Candidates for PGS
1) There have been two or more failed IVF attempts
2) There is a history of repeated miscarriages(two or more)
3) The woman is of advanced maternal age
4) Couples who desire single embryo transfer
How PGD/PGS performed?
1) Embryos are produced through IVF treatment
2) Each embryo is biopsied usually at the blastocyst stage(day 5)
3) The cell sample is analyzed for chromosomal or genetic abnormalities
4) Freezing of the embryos using of a method called vitrification
5) It takes over 24 hours before the results are available.
6) The final step is the thawing of the healthy embryos in a subsequent cycle and the transfer of them (or one in the case of single embryo transfer) back in the uterus.
