Description
Non-invasive prenatal DNA testing (NIPT) is a screening study aimed at detecting fetal chromosomal abnormalities, performed by analyzing cell-free fetal DNA in maternal blood. NIPT is a screening method for assessing the risk of the most common fetal chromosomal abnormalities: trisomy 21 (Down syndrome), trisomy 18 (Edwards syndrome), trisomy 13 (Patau syndrome), and sex chromosome aneuploidies. Depending on the fetal sex, the report indicates the risk of monosomy X (Turner syndrome) and trisomy X (XXX syndrome) for a female infant; disomy X (Klinefelter syndrome) and disomy Y (Jacobs syndrome) for a male infant. The test also detects the risk of microdeletion syndromes: 22q11.2 microdeletion (DiGeorge syndrome), 1p36 microdeletion (1p36 syndrome), 15q11-13 microdeletion (Angelman / Prader-Willi syndrome), 4p16.3 microdeletion (Wolf-Hirschhorn syndrome), 5p15 microdeletion (Cri-du-chat syndrome). Additionally, the risk of autosomal recessive diseases associated with maternal carriage of pathogenic genetic variants in the CFTR, PAH, GALT, GJB2, SLC26A4, TPP1, ATP7B, DARS2, DHCR7, HEXA, IDUA, PIGN, PKHD1, PMM2, SLC26A2, USH2A, SMARCAL1, ALDOB genes is determined (other genes and genetic variants may also be included in the study).
The test analyzes embryonic-placental cell-free DNA isolated from maternal plasma. The risk of genetic disease in the child is assessed. The study makes it possible to suspect certain disorders and syndromes and, knowing about them, to provide timely treatment for the born child. It should be noted that this is a screening test, meaning a diagnosis cannot be made based on its results. It assesses the probability of chromosomal pathologies but does not allow them to be unequivocally diagnosed, even when a high risk is identified. The result of this test is not a diagnosis but only a statistical probability figure. When using a donor egg or in surrogacy, determining carrier status for autosomal recessive mutations is uninformative without providing a blood sample from the biological mother. The test is performed from the 10th week of pregnancy in the absence of ultrasound signs of chromosomal pathology. Gestational age must be established by ultrasound data.
Prenatal genetic testing assesses the risk of chromosomal abnormalities. If there is a risk of disorders, one can be prepared for the diagnosis and arrange in advance to provide specialized support and medical care for the child. With current medical capabilities, a fairly high quality of life is possible for many congenital pathologies.
Detection of an increased risk of fetal malformations is not a diagnosis. False-positive results are possible.
Testing for sex chromosome aneuploidies, as well as determining the sex of the future child, is possible only in singleton pregnancies and at the patient's request.
Limitations of the method:
aneuploidies of other autosomes (chromosomes) are not detected;
maternal chromosomal abnormalities or chromosomal mosaicism;
gestational age less than 10 weeks at the time of blood collection for the study;
singleton pregnancy that began as a twin pregnancy ("vanishing twin");
blood transfusion within the last 3 months;
prior organ, bone marrow, or stem cell transplantation (in these cases, the risk of a false test result is increased);
presence of oncological disease;
in pregnant women with obesity, the concentration of the fetal DNA fraction is reduced due to a larger volume of circulating blood, which may lead to false results.
Period of execution
Within 14 days
Biomaterial type