What is Preimplantation Genetic Diagnose (PGD)

Many of couples have genetic disorder, and they have high risk of transmitting the genetic disorder to their offspring. Since now there was no technique to detect the same prior to the pregnancy being achieved. Preimplantation Genetic Diagnose (PGD) is new hope to detect the genetic disorder.


Preimplantation genetic testing is a technique used to identify genetic defects in embryos created through in vitro fertilization (IVF) before pregnancy. Preimplantation genetic diagnosis (PGD) refers specifically to when one or both genetic parents has a known genetic abnormality and testing is performed on an embryo to see if it also carries a genetic abnormality. In contrast, preimplantation genetic screening (PGS) refers to techniques where embryos from presumed chromosomally normal genetic parents are screened for aneuploidy.

Because only unaffected embryos are transferred to the uterus for implantation, preimplantation genetic testing provides an alternative to current post conception diagnostic procedures (ie, amniocentesis or chorionic villus sampling), which are frequently followed by the difficult decision of pregnancy termination if results are unfavorable. PGD and PGS are presently the only options available for avoiding a high risk of having a child affected with a genetic disease. It is an attractive means of preventing heritable genetic disease before implantation, thereby eliminating the dilemma of pregnancy termination following un-favorable prenatal diagnosis.


Primary candidates for PGD include the following:

• Couples with a family history of X-linked disorders (Couples with a family history of X-linked disease have a 25% risk of having an affected embryo [half of male embryos].)
• Couples with chromosome translocations, which can cause implantation failure, recurrent pregnancy loss, or mental or physical problems in offspring
• Carriers of autosomal recessive diseases (For carriers of autosomal recessive diseases, the risk an embryo may be affected is 25%.)
• Carriers of autosomal dominant diseases (For carriers of autosomal dominant disease, the risk an embryo may be affected is 50%.)