Preimplantation Genetic Testing (PGT)
Preimplantation Genetic Testing (PGT) is a procedure used to identify genetic defects within embryos (an egg fertilized with a sperm) before they implant in the uterus and develop into a pregnancy. This serves to prevent certain genetic diseases or disorders from being passed on to the child. The embryos used in PGT are created during the process of in vitro fertilization (IVF).
In Vitro Fertilization is an assisted reproductive technology, commonly referred to as IVF. IVF is the process of extracting eggs, retrieving a sperm sample and then combining an egg and a sperm outside of the body in a laboratory dish in order to create an embryo.
- After the egg is fertilized, the embryo divides into many cells over the following 3 to 6 days.
- On day 5 or day 6 of development, the embryo usually reaches the blastocyst stage. At this stage, the embryo usually contains approximated 100-120 cells. With PGT, approximately 4-8 cells are removed (commonly referred to as a biopsy) from the outer layer of cells. After this cell collection, the embryos are safely frozen until the results of the biopsy can be determined.
- The DNA of the cells from the biopsy is then evaluated to determine if the inheritance of a problematic gene or condition is present in the embryo. This process usually takes 1-2 weeks.
- Once PGT has identified an embryo(s) free of genetic problems, the embryo(s) will be placed in the uterus (an embryo transfer). Approximately 2 weeks later, a pregnancy test will determine whether the embryo implanted and is continuing to develop into a pregnancy in the body.
- Any additional embryos that are free of genetic problems are kept frozen for possible later use while embryos with the problematic gene(s) are discarded.
From starting the egg retrieval process to the final results of PGT generally takes 4 weeks. This does not include the time it may take to undergo initial testing, preparation and consultation with a fertility specialist. If PGT is necessary to test for a known genetic mutation, for example in ABCD1, additional time is often necessary to create the specific test (probe) necessary to identify the mutation in the embryo. It is important to keep this in mind if you plan to pursue IVF with PGT so that you know what to expect!
Cost $15,000 - $30,000 per cycle
54% Delivery Rate (pregnancy rates with genetically normal embryos are approximately 65%-70%)
Many insurance plans cover IVF and PGT or some portion of the process, but many do not.