What Is Non-Invasive Prenatal Screening?

3 minutes

Non-invasive prenatal screening is testing that allows us to rule out chromosomal anomalies that can affect the health of our babies. What do we need to know about this testing?

What Is Non-Invasive Prenatal Screening?

Last update: 27 December, 2018

Women should undergo a series of tests during pregnancy to assure that their babies are developing correctly. Through these diverse evaluations, doctors track the health of pregnant mothers and developing babies. Such is the case with non-invasive prenatal screening.

Non-invasive prenatal screening

Non-invasive prenatal screening also refers to a lab test that helps calculate the changes of there being trisomy in the chromosomes 13, 18, 21 and Y. The test uses fetal DNA from the mother’s blood.

With the latest advances in medicine, women can undergo this testing as early as the 10th week of pregnancy. The results are available 7 days later, and are 97% accurate.

Just as the name implies, this test in non-invasive. That means there is no need to perform an extraction of amniotic liquid – the liquid that surrounds the fetus in the uterus. Nor does it involve the introduction of needles into the abdomen to extract any other liquid.

“Non-invasive prenatal screening has been developed to carry out a more precise prenatal analysis of women of any age and risk group”

What does the testing entail?

To carry out non-invasive prenatal screening, specialists observe a sample of fetal blood cells that have accidentally passed from the fetus to the mother’s blood .

Through the observation of these cells, doctors can rule out the main chromosomal anomalies. These include the following:

Trisomy 21, known as Downs Syndrome
Trisomy 18, known as Edwards Syndrome
Trisomy 12, known as Patau Syndrome
Y-chromosome infertility, known as Jacob’s Syndrome

When the test result is negative, then there are few chances that your baby suffers from a chromosomal disorder. If, however, the test is positive, doctors will likely recommend retesting.

If tests come back positive a second time, they should be confirmed, according to the indications of your OB/GYN, through an amniocentesis or chorionic villus sampling .

When is non-invasive prenatal screening recommended?

It’s vital to take into account that each exam that a mother undergoes should be approved by a specialist and take place under medical observation. In general, doctors recommend prenatal screening in any of the following cases :

Women who have had previous pregnancies with Down Syndrome or another type of anomaly.
When both parents are carriers of a recessive autosomal disease. This is one of several ways in which a characteristic, disorder or illness can pass from parents to children.
If one of the parents is a carrier of some karyotypic disorder. This refers to the graphic presentation of chromosomes.
The mother is at least 35 years old.

The aspect that stands out most in this exam is that, unlike other prenatal diagnostic studies, there are no risks. This applies both to the fetus and to the mother .

The results of prenatal diagnosis

Once a woman has undergone non-invasive prenatal screening, she can resume daily activities. However, she should avoid overexertion. Normally, doctors recommend waiting a few days before having sexual intercourse.

It’s important for women to be patient and try not to become anxious if tests come back positive. Staying calm is vital, as is repeating the test.

It’s also important to remember that if the result is high-risk, then a specialist should confirm it through amniocentesis or chorionic villus sampling. Of course, as long as the gynecologist recommends it.

Prenatal screening helps us to observe fetal development and health early on. Therefore, it’s extremely important to undergo these studies and eliminate any sort of doubt that may arise during the gestation period. That way, parents can rule out anomalies and enjoy this period without any worries.