Preimplantation Genetic Diagnosis (PGD)

Preimplanation Genetic Diagnosis (PGD), first developed in the 1980's, is the application of genetic testing on a live embryo to determine the presence, absence or change in a specific gene or chromosome prior to the placement of the embryo in the womb.
PGD is preformed during IVF after collection of eggs and fertilisation, but before they are transferred back into the patients uterus. When the fertilised egg has reached somewhere between the 4- and 10-cell stage of development (usually the 8-cell stage, around day 3), a hole is made in the shell of the embryo and a pipette is used to gently remove one cell on which testing will be done. This technique is called embryo or blastomere biopsy. The removal of these cells does not appear to be detrimental to the development of the embryo. The 'sampled' embryo can then be grown a little longer in culture to let it recover from the procedures and to allow time for the genetic testing of its removed cells to take place. The DNA is removed from the cell and tested for the genetic disease or disorder. It may also be checked for overall chromosomal normality. Any diseased or abnormal embryos are destroyed. Testing usually takes a day to complete and the next day the healthy embryos are ready for transfer back into the patient's uterus.

Recurrent Miscarriage

PGD may ease miscarriage risk in older patients, studies have shown that 90% of miscarriages are due to chromosomal disorders, . And it appears that this occurs more often in older women. In younger women, these chromosomal abnormalities occur in about half of all embryos, but that climbs to an overwhelming 90% in women who are 35 plus. Although repeat pregnancy loss-defined clinically as a minimum of three miscarriages occurring consecutively-may occur due to hormonal, anatomic, or immunologic causes, the exact reasons haven't been uncovered in 50% of cases. Still, genetics may play a large role. At least 50% to 60% of early losses show a number of genetic abnormalities.

PGD can be tested for:

• Family Balancing
• Hemophilia
• Huntington's Disease
• Sickle-Cell Anaemia
• Chromosome Translocation
• Irreversible vasectomy
• Down's Syndrome
• Breast And Ovarian Cancers