The test limitations underlined here are meant for physicians use only, not intended for patients.
The process involved in embryo culture and biopsy are subject to various limitations including embryo quality, biopsy quality, DNA integration, maternal contamination, and many other factors that may compromise the quality of the PGT test. Like any medical test, PGTA has a low rate of false positive and false negative results, leading to misdiagnosis. Some of the reasons for misdiagnosis are associated with “mosaicism”, where chromosomally normal and chromosomally abnormal cells coexist in the same biopsy. Other sources of misdiagnosis could be related to contamination of maternal origin. In this case cumulus cells present the culture media or attached to the embryo can contaminate the biopsy leading to opposite gender or masking chromosomal abnormalities. PGT-A and PGT-M/PGT-SR are also complicated tests that use techniques that are at the limits of medical diagnostic testing therefore, PGT-A is not 100% error free. As a consequence, a normal result does not guarantee a chromosomally normal offspring. Embryos resulted as euploids may carry an abnormality that can lead to implantation failure, miscarriage, or birth with syndrome. This test is for pre-implantation embryo screening and is not intended as a replacement for conventional NIPT, CVS or amniocentesis performed during pregnancy. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. Follow-up screening during pregnancy is recommended.
PGT-A test evaluates chromosome copy only. It is designed for chromosome aneuploidy screening and not for the diagnosis of single gene disorders (PGT-M), including single or multiple nucleotide substitution, deletion, duplication, gross chromosomal changes such as large deletions, duplications, translocations, and inversions.
This test is limited to screening for aneuploidies greater than 20MB in size, it is not intended for detection of microdeletions or duplications, smaller gene duplications and deletions.
To learn more about PGT limitations, seek additional information from genetic counselors. Progenesis offers pre and post genetic counseling sessions, however it is the decision of the physicians and patients to choose their preferred genetic counselors. To address various topics, including family and pregnancy history, genetic testing options, understanding the test results, and making informed clinical decisions. Genetic counseling is available through the Revela portal. We have partnered with a team of genetic counselors who can provide valuable support and guidance throughout your IVF journey, ensuring you have the necessary information to make well-informed decisions.