PGD PREIMPLANTATION GENETIC DIAGNOSIS (Pre Genetic Diagnosis)
Preimplantation Genetic Diagnosis (PGD) is one of the most advanced scientific techniques in the field of assisted reproduction by which we control embryos for specific genetic or chromosomal abnormalities. This allows the selection of healthy embryos prior to implantation and leads to pregnancy with healthy embryos.
Pre-implantation Genetic Diagnosis has an indication if:
- the couple already has a child with a hereditary genetic condition,
- one of the two parents has a known family history of chromosomal damage;
- there are proven chromosomal abnormalities in previous miscarriages;
- the mother’s age is over 40 years old,
- couples with a history of repeated miscarriages,
- a history of repeated implantation failures following IVF.
What does pre-implantation genetic diagnosis include?
In preimplantation diagnosis on the 3rd day after fertilization, and when the embryo has 6-10 cells, the biologists remove a cell from the embryo with a very fine technique. These cells are analyzed by DNA and the result is available within 24 hours so that only normal DNA embryos will be implanted on the 5th day following ovulation.
With the latest human genome analysis (CGH-array) we are able to test for a very large number of individual gene disorders, such as:
- Mediterranean anemia
- Huntington’s disease
- Cystic fibrosis
- Duchenne muscular dystrophy
- Fragile-X syndrome
- BRCA1 / BRCA2 (heredity for breast / ovarian cancer)
- Screening when parents carry genetic translocations
- Screening when parents are carriers of reciprocal chromosomal translocations
The most common reason why couples in Greece resort to preimplantation diagnosis is when both are carriers of the thalassemia trait and want, without necessarily having a fertility problem, to have a perfectly healthy child. Dr. Ioannidis and the IVF of the MITERA maternity hospital is in collaboration with the Department of Pediatrics at the St. Sophia Children’s University Hospital and offers an innovative preimplantation diagnosis program for Cystic Fibrosis and B-Thalassemia. As early as 1998, the first child in embryonic stage was born in Greece and was pre-implanted for B-Thalassemia.
Sex selection can also be performed via pre-implantation diagnosis. Greek legislation prohibits sex selections for eugenic purposes or because the couple so wish, unless there are medical reasons, for example. transmission of a sex-linked disease. In other European countries, there is a strong debate about the selection of sex through preimplantation for non-medical reasons. The same is true if the preimplantation is performed to select an embryo histocompatible with its leukemia suffering sibling, in order to save this child through bone marrow transplantation.
The safety of a preimplantation diagnosis has been tested by many studies and it has been shown that the method is not harmful to embryos and that children born with this method are not different than children born after conventional IVF. The cell removed from the 6-10 cell embryo does not adversely affect the viability of the embryo.
If you or your partner know of a potential genetic disease in your family or you both have Thalassemia, you should discuss it with Dr. Ioannidis in order to undergo the necessary tests and decide if you need to go ahead with IVF and preimplantation genetic diagnosis.
Dr. Ioannidis manages an extensive pre-implant diagnosis program that has helped dozens of couples get healthy babies after long periods of infertility or with serious genetic diseases in the family.
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