Preimplantation Genetic Diagnosis (PGD)

Preimplantation Genetic Diagnosis (PGD) is an advanced genetic technique which allows an individual embryo to be analyzed. PGD is a recommended procedure for patients who are carriers of a genetic anomaly or are affected by a genetic condition that drastically reduces the probability of passing the anomaly to their offspring. Additionally, some patients with advanced maternal age or a history of recurrent miscarriages use PGD to select embryos that do not possess chromosomal abnormalities.

The technique of PGD involves the removal and analysis of a limited number of cells from a developing embryo. The analysis of these cells may be performed by fluorescent in situ hybridization (FISH) or polymerase chain reaction (PCR), which allows a geneticist to provide information on the individual embryo's chromosomal make-up. PGD cases require extended embryo culture (see Blastocyst transfer and culture) to allow for enough time for genetic analysis to be performed. In consultation with the patient's physician and embryology laboratory, the decision of which embryo(s) and how many embryos to transfer will be made.