Non-invasive prenatal tests - what are they? Taken at a certain stage of pregnancy, prenatal tests can detect serious malformations in a baby and genetic diseases before it is born. Thanks to this, it is possible to start treatment of the fetus in the womb or the newborn immediately after delivery. Equally important, non-invasive prenatal tests are completely safe for the developing baby. Check what non-invasive prenatal tests are, when to do them and what they are about.

Contents:

  1. Non-invasive prenatal tests: genetic ultrasound
  2. Non-invasive prenatal testing: double test
  3. Non-invasive prenatal testing: triple test
  4. Non-invasive prenatal testing: NIFTY test
  5. Prenatal tests: price

Non-invasive prenatal testsare tests that should be performed by some pregnant women .This especially applies to women over 35, and also those with previous genetic diseases in the family (or the child's father). Also ladies who previously gave birth to a child with a genetic defect (e.g. Down syndrome), central nervous system defect (e.g. hydrocephalus, cerebrospinal hernia) or with a specific group of metabolic diseases (e.g. cystic fibrosis).

Due to the fact that these tests are non-invasive, they will only allow to estimate the risk of developmental defects and genetic diseases. On their basis, no unequivocal diagnosis can be made. However, their advantage is that they do not carry any risk of complications. They differ from invasive prenatal tests, which allow for the precise determination of fetal disorders, but may have side effects, including pregnancy loss.

Non-invasive prenatal tests: genetic ultrasound

  • When is genetic ultrasound performed?

Genetic ultrasound is performed between the 11th and 13th week and the 6th day of pregnancy, and then between and between the 18th and 23rd week of pregnancy.

  • What is genetic ultrasound?

The doctor introduces a special ultrasound head through the vagina. The ultrasounds reflected from the fetus are processed into the image visible on the monitor. It can take up to half an hour to be precisely made. Depending on the momentdo the examination, the doctor may examine the gestational vesicle, the thickness of the fetal nape, the nasal bone, the phalanges of the hand, the outline and dimensions of individual organs. It can also evaluate the placenta, umbilical cord and amniotic fluid.

  • What diseases can it detect?

Ultrasound allows you to accurately assess whether a child has a genetic defect, such as Down's syndrome (detects about 80% of cases of this disease), Edwards' syndrome and Patau's syndrome (about 90% of detected cases), or Turner and malformations - e.g. neural tube or cleft palate.

Taken after the 20th week of pregnancy, it may contribute to the detection of congenital heart defects, which are formed by the 43rd day of pregnancy, but only at the end of the fifth month are large enough to be examined by ultrasound. After around 27 weeks of gestation, the developing skeleton and lungs make it difficult for ultrasound to reach the fetal heart.

Non-invasive prenatal testing: double test

  • When is the double-test performed?

The double test is performed between 10 and 14 weeks of pregnancy.

  • What is the Double Test?

The duplicate test measures the concentration of PAPP-A and the free beta hCG subunit (βHCG, or chorionic gonadotropin) in the blood, two hormones produced by the placenta during pregnancy. The results are analyzed by computer using a special program called the risk calculation module according to the FMF (The Fetal Medicine Foundation) standards.

  • What diseases can it detect?

Thanks to this prenatal examination, it is possible to detect genetic defects of the fetus, such as Down's syndrome, Edwards' syndrome, Patau's syndrome, other chromosomal abnormalities. This test only approximates the risk of birth defects in the fetus, so even a positive result does not mean that the child is sick, but that the risk of a genetic disease is high. However, if the result is positive, your doctor may order invasive prenatal tests, such as amniocentesis.

Non-invasive prenatal testing: triple test

  • When is the triple test performed?

The triple test is performed between 17 and 20 weeks of pregnancy.

  • What is the triple test?

The test consists in assessing the level of three substances in the blood: alpha-fetoprotein (AFP), chorionic gonadotropin (beta hCG) and estriol. The test results, your age and weight are entered into the computer. A special program compares this data with the data of a thousand he althy Polish women.

  • What diseases can it detect?

The test allows you to assess whether you are in a group with an increased risk of developing a genetic defect in the fetus. Incorrect (compared to he althy women) concentration of any of the tested substances is associated with a higher risk of occurrence, e.g. Down syndrome, Edwards', Turner or obstructive uropathies (the outflow of urine from the bladder is difficult, which results in, for example, serious kidney damage). In this case, the woman may also get a false-positive result, which means that despite the incorrect test result, there is no genetic defect.

Non-invasive prenatal testing: NIFTY test

  • When is the NIFTY test performed?

The NIFTY test is performed between the 10th and 25th week of pregnancy.

  • What is the NIFTY test?

The test consists in isolating the child's genetic material circulating in the mother's peripheral blood. It is then analyzed using advanced sequencing techniques.

  • What diseases can it detect?

The NIFTY test allows you to determine the risk of fetal trisomy, i.e. diseases such as, incl. Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), Patau syndrome (trisomy 13). This test is characterized by very high accuracy - over 99%. and a low percentage of false positives - less than 1%.

Prenatal tests: price

Prenatal tests may be reimbursed if the woman is at risk and has received a referral from a doctor who has a contract with the National He alth Fund.

The risk groups include:

  • woman's age - over 35
  • high genetic risk in the family
  • fetal chromosomal abnormalities that occurred in the previous pregnancy
  • occurrence of structural chromosomal aberrations in the family
  • occurrence of an increased risk of having a child with a multi-factorial or monogenic disease
  • abnormal ultrasound result
  • presence of abnormal levels of biochemical markers of well-being.

The cost of self-test prenatal tests varies in many cities. The average prices are as follows:

  • Genetic ultrasound, half ultrasound, third trimester ultrasound - about PLN 250
  • Double test (PAPP-A) - from PLN 250
  • Triple test - from 250 PLN
  • NIFTY test - from PLN 2,300

Price of invasive prenatal tests:

  • Amniocentesis - from PLN 1,300
  • Chorionic villus sampling - from PLN 1500
  • Cordocentesis - from PLN 1500

What does prenatal testing look like?

This question is answered by Dr. Piotr Dydowicz, obstetrician-gynecologist.

Category:

Pregnant examinations