Overview
Pre-implantation Genetic Diagnosis (PGD) is a technique to test embryos for serious inherited genetic disorders already affecting other family members, prior to implantation.
This has many advantages for a couple where they would find it hard to consider terminating an affected praegnancy after prenatal diagnosis at a later stage of pregnancy.
Q. What is PGD?
PGD is a procedure where a cell from the embryo can be tested for chromosomal and genetic abnormalities prior to placement into the uterus.
It is the earliest form of prenatal diagnosis screening carried out on a laboratory-created embryo.
The aim of PGD is to prevent embryos that are carrying a genetic abnormality from being transferred into the uterus. At this point, PGD is helpful if a couple has an increased risk of having a child with a specific genetic disorder, such as cystic fibrosis, Down syndrome or Turner’s syndrome.
Q. How is PGD Performed?
At IVFAustralia, genetic counselling is provided if a couple is considering PGD. This is to ensure the appropriate time is taken to consider all of the implications of PGD.
The woman will undergo a process similar to an IVF procedure, involving ovarian stimulation to allow multiple egg collection. Fertilisation is carried out by ICSI.
Three days after fertilisation, one or more cells are removed from the embryo. These cells are analysed for a specific inherited disorder or chromosome abnormality. Results are available on Day 5 following fertilisation and only healthy embryos are transferred into the uterus.
Q. Who should consider PGD?
At present, PGD is an evolving technique in fertility treatment. There is currently no evidence to suggest that PGD testing is helpful for screening all embryos. However, PGD is very valuable in identifying whether a particular embryo is carrying known hereditary conditions.