Fetal DNA test (NIPT): non-invasive prenatal screening

“The NIPT (Non-Invasive Prenatal Test) is currently one of the most modern and easiest prenatal screening tests to perform, thanks to its high sensitivity compared to traditional first-trimester tests, such as the double test or combined test.

The fetal DNA test allows a more accurate assessment of the risk of the main chromosomal abnormalities, in particular trisomy 21, which causes Down syndrome.

Unlike invasive procedures such as amniocentesis and chorionic villus sampling, which involve the direct collection of fetal cells from the amniotic fluid or placenta using a needle, NIPT carries no risk of complications for either the mother or the fetus, such as infections or rupture of the membranes.

It should be noted, however, that this is a screening test and not a diagnostic one. In the case of a ‘high-risk’ result, the gynecologist may recommend further investigations with invasive diagnostic tests, which can provide definitive confirmation of the presence or absence of a chromosomal abnormality,” states Dr. Sala.

NIPT allows the detection of:

• the main trisomies (21, 13, and 18);
• sex chromosome abnormalities;
• alterations of other chromosomes;
• specific genetic microdeletions.

“The test can be carried out as early as the 10th week of pregnancy. It offers very high reliability, making it the most advanced screening method currently available. It can be offered to all pregnant women, regardless of the type of conception or maternal age.”

It is prescribed by the gynecologist who follows the pregnancy and is responsible for prenatal diagnosis.

The NIPT procedure is simple:

• a venous blood sample is taken, like a routine blood test;
• the sample is sent to a specialized laboratory;
• results are available within a few days.

The test involves no risk or stress and, for many expectant mothers, especially those who have undergone medically assisted reproduction (MAR), it represents a moment of reassurance and greater awareness.

The testing pathway also includes an informational consultation, during which the physician explains the purpose and limitations of the test, and the patient’s informed consent prior to testing.

No special preparation is required: fasting is not necessary, and there is no need to discontinue any medications or ongoing treatments.

“It is, however, important to report any relevant information, for example:

• if the patient has undergone medically assisted reproduction (MAR) or heterologous fertilization such as egg donation or embryo donation;
• if the pregnancy is a twin pregnancy;
• if there is a ‘vanishing twin,’ meaning a twin that was lost in the early weeks of pregnancy.

These details help the laboratory interpret the results correctly.”

After a journey of medically assisted reproduction (MAR) (often long, deeply desired, and emotionally intense) peace of mind and a sense of security are fundamental for new parents.

“For this reason, it is always recommended, especially for women who achieve pregnancy through MAR, to undergo the fetal DNA test, as these pregnancies, due to the generally higher maternal age, are associated with an increased risk of developing aneuploidies,” concludes Dr. Sala.