What Does Pre-Implantation Genetic Diagnosis Mean?
Preimplantation Genetic Diagnosis (PGD) Benefits & Concerns
Preimplantation genetic diagnosis (PGD) is a reproductive technique used alongside in vitro fertilization (IVF) to help identify genetic defects within embryos. This serves to prevent certain genetic diseases or disorders from being passed on to the child. The process helps potential parents prevent the birth of a child with a serious genetic condition. The embryos used in PGD are usually created during the process of in vitro fertilization. This article is not the end-all-be-all of PGD. The information below is designed to help you ask the important questions when discussing the options you have with your healthcare providers.
How is the PGD performed?
Beginning with the normal process of in vitro fertilization, the egg is retrieved and fertilized in a laboratory. Once fertilized, the embryos develop and multiply for 5-6 days. A portion of cells are removed from each embryo. After which, the embryos are safely frozen. Then, the DNA of the cells is tested for genetic or chromosomal abnormalities and evaluated to determine if the problematic gene is present in the embryos. This process takes at least one full week. Once PGD has identified embryos free of genetic problems, the unaffected embryo(s) will be placed in the uterus (usually by an IVF procedure). After implant, the wait for a positive pregnancy test begins. If successful, the procedure will result in pregnancy and a child not affected by the condition for which it was tested. Any additional embryos that are free of genetic problems are kept frozen for possible later use, and embryos with the problematic gene(s) will not be transferred.
Getting from the egg retrieval process to the final results of PGD can take several weeks. This process includes collection, fertilization, 3-5 days of development, 1-2 weeks of testing, and scheduling an appointment to discuss results with your doctor. It is important to keep time in mind when planning to pursue IVF with PGD.
How Can I Benefit from PGD?
Preimplantation genetic diagnosis can benefit any couple at risk for passing on a genetic disease or condition to their children. Parents may have the condition themselves or are just carriers of the genetic condition. If you already have a child affected or may have experienced the loss of a child or pregnancy due to a condition or disease, preimplantation genetic diagnosis may be right for you.
Possible Candidates for PGD Include:
- Carriers of single gene disorders for which PGD testing is available.
- Those with chromosomal disorders, including inversions, deletions, aneuploidy (an abnormal number of chromosomes), and translocations.
- Sex-linked conditions, for which it is not yet possible to test for the specific genetic mutation, but can test for sex rather than mutation. Because of this, preimplantation genetic diagnosis has also been used for the purpose of gender selection.
- Women over the age of 35.
- If you or your partner has a family history of a serious genetic condition.
Pros and Cons of PGD
Although controversial to some, preimplantation genetic diagnosis has the potential to detect gene mutations and disorders. The benefits of using PGD allows the embryo to be tested for more than 100 different genetic conditions. Keep in mind that preimplantation genetic diagnosis does not replace the recommendation for prenatal testing, nor alter any DNA. The procedure is performed before implantation to allow the couple to decide if they wish to continue with the pregnancy. While PGD helps reduce the chances of conceiving a child with a genetic disorder, it cannot completely eliminate this risk. In some cases, further testing is needed during pregnancy to assess if a genetic abnormality is still possible.
Preimplantation Genetic Diagnosis in New York
Preimplantation genetic diagnosis has helped thousands of families increase their chances of conceiving a healthy baby. If you or someone you know are struggling with pregnancy, NYU Langone Reproductive Specialists of New York is the place for you. With offices in offices in Mineola, Stony Brook, West Islip, and Brooklyn, we are determined to help you succeed. For more information about preimplantation genetic diagnosis or any of the other services we provide, contact us and book an appointment. We look forward to hearing from you!