Roughly 85% of Donor Nexus’ intended parents choose to have PGT-A testing performed on their embryos.
PGT-A, formerly preimplantation genetic screening (PGS), is a procedure that can be done before embryo transfer to test for chromosomal abnormalities. This procedure involves the culturing of embryos to the blastocyst stage and a biopsy to allow for the testing of a sample of cells from the embryo. This process is completed without damaging the embryo, so it can be utilized for transfer back to effect a pregnancy once the results are known.
PGD stands for preimplantation genetic diagnosis. This test is useful for patients who wish to screen their embryo(s) for a specific genetic condition, like Tay-Sachs, Sickle Cell Anemia, or Cystic Fibrosis, among many others. Generally, PGD testing is recommended for individuals with a family history of disease and individuals who are concerned that they may be carriers of genetic disease. PGD testing is 98% accurate in identifying affected and unaffected embryos for approximately 2,000 inherited single-gene disorders.
PGT-A and PGD are tested in similar ways. After the IVF process takes place and the embryos are grown to approximately day 5 blastocysts, a small number of cells are retrieved from each embryo and sent to a laboratory for testing. This process is completed without damaging the embryo.
Depending on your clinic, the embryo(s) may be frozen at this stage while we wait for the genetic testing results, requiring you to have a frozen embryo transfer. Some clinics are now offering fresh Day 6 transfers of PGT-A tested embryos. You should inquire with your fertility clinic to find out if they offer fresh embryo transfers with PGT-A.
Once the testing is complete, a report is sent to your fertility specialist who will be able to make more informed decisions about which embryos should be transferred, giving you the best chance for a successful pregnancy. The results from PGT-A/PGS and PGD testing can take anywhere from 12 hours to a month, depending on the laboratory.
The number one failure of IVF is chromosomal abnormalities of the transferred embryos which frequently results in miscarriage. By performing PGT-A, we can ensure the embryos are genetically normal before transfer, thus, greatly reducing the chance of miscarriage during the first trimester. Using PGT-A or PGD can increase the likelihood of a successful pregnancy and decrease the chances of a genetic disease. Prenatal diagnostic testing can help confirm the results of PGT-A/PGS or PGD after conception has occurred.
Overall, preimplantation genetic testing can help ensure that you are transferring a genetically normal embryo. Additionally, sex chromosomes are identified through PGT-A so this is beneficial for patients who may be interested in gender selection.
Your fertility specialist will let you know whether PGT-A and/or PGD are recommended based on your individual needs. If you have any questions, our team will be happy to help in any way we can.