Preimplantation Genetic Diagnosis (PGD)

PGD is a procedure performed on embryos to assist detection of known genetic diseases or chromosomal abnormalities. PGD combines the existing technology of IVF (in vitro fertilization) and micromanipulation (ICSI, embryo biopsy) with molecular genetic techniques. A growing list of conditions, where the abnormal gene is known, can be diagnosed using PGD, Including Achondroplasia, Sickle cell disease, Cystic Fibrosis and Huntington's Disease.

PGD Procedure

Couples who have PGD will undergo an in vitro fertilization (IVF) cycle to create an embryo. The embryo will undergo a biopsy around the third day of its development when it has approximately 6-8 cells. A single cell is removed from the embryo using small instruments referred to as pipettes. DNA is retrieved from this cell and copied through a process known as polymerase chain reaction (PCR). A molecular analysis evaluates the DNA sequence code to determine the inheritance of the gene is present.

Once the PGD procedure has been performed and embryos free of genetic problems have been identified, implantation will be attempted through embryo transfer, intracytoplasmic sperm injection (ICSI) or Zygote Intrafallopian Transfer (ZIFT).

Who is at risk?

• Older women with previous miscarriage or previous failure to become pregnant with IVF
• Women with recurrent miscarriages
• Any couples with repeated failure to get pregnant with properly performed IVF cycles
• Couples in whom the man's sperm production is so low that we have to operate on the testis to retrieve sperm for IVF.