PGD PGD
Preimplantation genetic diagnosis (PGD) is a diagnostic test used in conjunction with in vitro fertilization (IVF) performed on embryos to assist detection of known genetic diseases or chromosomal abnormalities. Since it was first performed in 1989, PGD has become the most important advance in genetic testing to assure babies are born without genetic abnormalities. Couples known to have serious genetic disorders or who carry a genetic disease have successfully decreased the likelihood of having a child with these life-threatening inflictions.
A single cell is removed from an embryo and analyzed for a specific abnormality. PGD allows RSC’s team to identify embryos with irregularities. By transferring only non-affected embryos to the mother’s uterus, the probability that couples will have a healthy child increases.
Prior to the use of PGD, genetic disease diagnosis was limited to testing a fetus through amniocentesis or chorionic villus sampling. PGD provides a couple with more conclusive information about the health of the fetus. Knowing the genetic health of the fetus provides a couple with the tools to make informed decisions about the path a pregnancy should take.
RSC is pleased to offer PGD to our patients. Embryo genetic testing is coordinated through RSC’s PGD team chair, Dr. Susan P. Willman and Dr. Kristen Ivani, IVF Lab Director. Dr. Ivani received her doctorate from the department of physiology at Colorado State University. In addition to her work with PGD, Ivani’s other areas of interest include embryo cryopreservation and gamete micromanipulation. Dr. Ivani’s work has been instrumental in advancing the field of PGD, including the recent introduction and use of laser technology to facilitate embryo biopsy.
Genetics 101
What Causes Genetic Defects?
Cells contain chromosomes, string-like structures that contain all of our genetic material, called genes. Genes are made up of DNA sequences. Each cell has approximately 30,000 genes. Genetic disease is caused by abnormalities of gene function. This occurs when there are too many or too few chromosomes (aneuploidy), chromosome pieces are attached to the wrong chromosome (translocation), a piece of a chromosome is missing (deletion), part of a chromosome is upside down (inversion), or the gene's DNA sequence is changed.
Indications for PGD
Infertility & Recurrent Miscarriage
PGD is most frequently recommended for patients who are at risk for genetic disorders such as cystic fibrosis, Tay Sachs disease, or thalassemia. PGD is also helpful for patients with unexplained infertility, recurrent miscarriages, unsuccessful IVF cycles, advanced maternal age, or male factor infertility. In these cases, the most likely cause is a chromosome abnormality.
Preimplantation Genetic Diagnosis (PGD) Procedures
PGD is only performed on embryos in vitro (in a laboratory). That means this test is always performed in conjunction with an in vitro fertilization (IVF) cycle.
