Non-invasive prenatal test (NIPT)

Test for the screening for Down syndrome (trisomy 21), Edwards syndrome (Trisomy 18) and Patau syndrome (trisomy 13) in the baby by measuring DNA of the baby in the blood of the mother.


Centre for human genetics

Even during the Covid-19 crisis, you can count on us to make every effort in order to provide you with the service that you are entitled to. We have therefore taken all necessary measures to guarantee the continuity of our NIPT services.


Detection in the blood of the mother

NIPT is a non-invasive screening test for the detection of:

  • Down syndrome (trisomy 21)
  • Edwards syndrome (trisomy 18)
  • Patau syndrome (trisomy 13)

Are you considering NIPT for other reasons? You should first discuss this with your doctor. For other specific genetic disorders, an alternative type of genetic testing may be more appropriate.

How does the NIPT work?

  • DNA of the baby circulates in small quantities in the blood of the mother.
  • In general, sufficient DNA of the baby is present from 12 weeks of gestation onwards.

The NIPT determines:

  • Whether or not there is an extra copy of chromosome 21, 18 or 13.
  • The sex of the baby.


  • Detection via blood sampling in the mother from 12 weeks of gestation onwards.
  • No risk for a miscarriage.
  • No risk for you or your baby.


  • Since November 2013, more than 75,000 analyzes have been completed successfully in our center.
  • NIPT has an unprecedented sensitivity of almost 100% for detection of trisomy 21, 18 and 13.
    • NIPT is therefore much more reliable than the combined test.
  • In rare cases, the NIPT result is false positive.
    • In this case the test results indicate that the baby has a trisomy, whereas this is not true.
    • An abnormal test result should therefore always be confirmed by an invasive test (preferably by amniocentesis).

The NIPT performed within the Center of Human Genetics in Leuven is an in-house optimized and validated test and has been published in various scientific journals. The laboratory was accredited for this according to the ISO 15189 quality standard via BELAC (215-MED).

As a genetic center, we also provide multidisciplinary expertise that guarantees the correct interpretation and follow-up of the NIPT in accordance with the national guidelines of the Belgian Society of Human Genetics (BeSHG) and the advice of the Belgian Advisory Committee on Bioethics (Opinion No. 66).

Rare incidental findings

Using NIPT, all chromosomes are analyzed. Therefore, in rare cases, NIPT can also detect other chromosomal abnormalities, for example:

  • A trisomy of a chromosome other than 13, 18 or 21 (frequency: ~1/300 of the analyzes performed).
  • A chromosome abnormality in the mother that is important for her own health or for that of her baby.
  • Some types of cancer in the mother.

In either one of these cases, your doctor will inform you accordingly.


  • From the 12th week of gestation onwards.
  • If, during this pregnancy, a combined test or NIPT has not already been performed and reimbursed by the public health insurance.

Please provide the following information on the request form for correct interpretation of the test results:

  • Monozygotic or dizygotic twin pregnancy or multiple pregnancy (identical and non-identical twins).
  • Pregnancy with a ‘vanishing twin’ (original twin pregnancy with one baby deceased early in pregnancy).
  • The weight of the mother prior to the pregnancy exceeded 100 kg.
  • The mother has (had) cancer.
  • The mother has (had) lupus.
  • The mother is/was on heparin therapy.


NIPT is not appropriate in case of:

  • Ultrasound abnormalities in your baby (including a nuchal translucency of >3.5mm).
  • The mother has had one of the following treatments:
    • Stem cell therapy
    • Organ transplant

Limitations of NIPT

NIPT is not able to detect:

  • Mosaic trisomy 21, 18 or 13 (not all the cells have a trisomy)
  • Small chromosome abnormalities (microdeletions or microduplications)
  • Monogenic (single gene) disorders (such as cystic fibrosis or fragile X syndrome)
  • Numerical abnormalities of the sex chromosomes (such as Turner syndrome or Klinefelter syndrome)


The result will be available within a maximum of 7 calendar days from the receipt of the blood sample in our laboratory.

The results can be consulted in your online medical file through ‘mynexuzhealth’. You will also receive a hard copy of these results. In case of an abnormal result, your doctor or the Centre of Human Genetics will inform you.

Possible test results

  • Normal: there is no indication for the presence of trisomy 21, 18 or 13 in the baby.
  • Abnormal: there is a strong suspicion of the presence of trisomy 21, 18 or 13 in the baby.
    • To have complete certainty, an abnormal NIPT result should always be confirmed by an invasive test, preferably amniocentesis.
  • Inconclusive: rarely, the NIPT result cannot exclude nor confirm the presence of trisomy 21, 18 or 13 in the baby. In this case, further follow-up is recommended, either by a new NIPT analysis on a second blood sample (at no additional cost), or additional ultrasound followed by an invasive test (amniocentesis).
  • No result: exceptionally, the NIPT fails. If this is due to technical issues, the NIPT can be repeated once on a second blood sample (at no additional cost), or you can opt for another test.


NIPT is reimbursed in Belgium.

  • Hence, pregnant women who are a member of a Belgian service for public health insurance only pay € 8.68 for the laboratory test.
  • In case of an increased allowance, the NIPT is free of charge.
  • In other cases, your personal cost for the laboratory test is € 263.25.

For a genetic consultation, an additional cost will be charged.

  • In case you are a member of a Belgian service for public health insurance, the additional cost is € 12.
  • In case of an increased allowance, the additional cost is € 3.
  • In other cases, an additional € 39.38 will be charged for the genetic consultation.

For professionals


Extra information

Last edit: 19 February 2021