Prenatal diagnostic tests (cordocentesis, amniocentesis, etc.) can sometimes be requested by specialist physicians, during check-ups of a pregnancy whether the patient fell pregnant naturally or via IVF.
Although these tests give comprehensive information about the genetic structure of the foetus, there are risks involved (pregnancy loss, infection, etc.) because the procedure itself is a biopsy carried out. The biopsy is when cells are needed to be obtained from the fluid in the womb; the risk of the pregnancy ending is low but yet still present.
Scientific studies in recent years show that, a number of cells from the foetus can enter into the mother’s blood circulation following the first weeks of the pregnancy, and these cells and their genetic material of these cells (DNA) are also present in the mother’s blood during the pregnancy.
The technique of Non-invasive prenatal diagnostics allows us to assess the foetus and specific chromosomes in the early stages of pregnancy (from the 10th week), the cells collected from the womb allows us to perform genetic testing.
Chromosome anomalies that are the most common in pregnancy are:
- Trisomy 21-Down syndrome;
- Trisomy 18-Edwards syndrome;
- Trisomy 13-Patau syndrome
Anomalies related to the sex chromosomes are:
- Klinefelter Syndrome (XXY);
- Turner syndrome (X0))
And certain micro-deletions (Cri-du-chat, etc.) associated with diseases can also be detected in the early stages, minimising the risk of miscarriage via the NIPD test.
How is the test performed?
The only material required for the test is 18-20 cc of blood taken from the mother. The blood is extracted and placed into specially designed tubes. It takes up to 3 weeks for the results to be clear and carries an accuracy rate of 98%.
The present pregnancy is reported at the end of an examination period of 2-3 weeks in terms of examined genetic diseases with a share of over 98% accuracy. The results can be obtained before the application of amniocentesis testing is needed.
NIPT tests are used but under different product names such as NIFTY, Harmony or Panorama testing. Some of these tests state that they are able to scan for certain chromosomal micro-deletions which can mean the detection of high-risk chromosomes that would result in babies being born with a serious disease if undetected. It is recommended that you seek genetic counselling and consultation with a specialist before seeking any kind of testing.
If the findings after NIPT tests come back as Low-risk, this does not mean that the baby is completely genetically healthy as the test is only a screening of specific chromosomes and/or DNA areas. However, it is extremely important in terms of evaluating serious chromosomal abnormalities (such as Down syndrome) that can be detected very early in the pregnancy.
NIPT testing is very new and is not considered as diagnostic tests as yet, so doctors use the NIPT testing at their discretion. Results have shown that since testing there has been a significant decrease in the amount of amniocentesis being carried out.
NIPT tests is not only a test that can be applied to singleton pregnancies, it can also be applied in twin pregnancies with accurate results.