NIPT – Non-Invasive Prenatal Test

The NIPT (Non-Invasive Prenatal Testing) is a non-invasive screening test for pregnancy, based on the analysis of free DNA in the maternal circulation, and is used to detect fetal chromosomal abnormalities. NIPT analyzes free DNA in the maternal circulation, which includes a portion of DNA of maternal origin and a portion of DNA of placental origin. The Non-Invasive Prenatal Test analyzes the presence of any variations in fetal DNA concentrations, providing an estimation of the risk for certain chromosomal abnormalities.

Although characterized by high sensitivity and specificity, the NIPT Test does not have diagnostic value but provides a risk prediction: results can indicate “low risk” or “high risk” for each of the studied chromosomal abnormalities. In cases of a high-risk result for a particular chromosomal anomaly, confirmation analysis through diagnostic testing is always recommended. Confirmation testing can be performed on samples of chorionic villi or preferably amniotic fluid, obtainable through invasive methods (amniocentesis/chorionic villus sampling).

For each type of NIPT test, it is possible to associate preconception genetic screening for couples. The screening involves analyzing the couple for some of the most common conditions with carriers in the Italian population:

• Cystic Fibrosis (CF)
• Non-syndromic deafness linked to connexins
• Spinal Muscular Atrophy (SMA)
• Fragile X Syndrome

Once performed, it is not necessary to repeat preconception genetic screening for subsequent pregnancies. The test involves a blood draw for both parents to assess carrier status for the aforementioned conditions.

In the case of both parents being carriers of the same condition (CF, deafness, and SMA) or the mother being a carrier of Fragile X (X-linked condition), amniocentesis is recommended to verify the fetal genetic makeup for the specific condition under examination.

When is NIPT recommended?

NIPT represents a valid alternative/supplement to screening methods applied during pregnancy (such as bi-test, tri-test, etc.). As per guidelines, it is recommended to associate the test with ultrasound measurement of nuchal translucency and pregnancy monitoring according to the indications of the attending specialist.

Why choose it during pregnancy?

NIPT is a non-invasive screening test that poses no danger to either the mother or the baby and has high accuracy in detecting the presence of three copies of chromosomes 21, 18, and 13, trisomy associated with Down syndrome, Edwards syndrome, and Patau syndrome, respectively.

How is NIPT performed at Arsbiomedica Clinic?

For NIPT, a maternal blood draw is necessary, preferably between the 11th and 14th week of gestation.

In some cases (about 1-2%), the concentration of free fetal DNA circulating may be too low to be analyzed. In such cases, a repeat blood draw will be offered free of charge.

However, it is possible that repeating the test may not yield a result. The test can produce false positive and false negative results, so it is important for the results to be interpreted by the referring specialist in the context of a comprehensive evaluation of the pregnant woman’s clinical and medical history.

How to prepare for the NIPT Test

Fasting is not necessary for NIPT. Before and after the test, consultation with a Geneticist is scheduled to provide all the necessary information.

It is recommended to provide clinical reports related to the ongoing pregnancy (ultrasounds, nuchal translucency measurement, bi-tests, etc.), any family genetic diseases, and any previous genetic tests.