It is an advanced blood test used to detect trisomies in all singleton and twin pregnancies after the 10th week of pregnancy. It strongly indicates whether you are at high or low risk of having Trisomy 18
(Edwards syndrome) or Trisomy 13 (Patau syndrome).
What is Trisomy 21, 18 or 13? ?
Humans have 23 types of chromosomes, and in most people, each of these chromosomes is a pair. (hence 46
chromosomes in total) Trisomy is when the number of chromosomes that should be two is three (total of 47
chromosomes). The most common trisomies are chromosomes 21, 18 and 13.
Trisomy 21 occurs in approximately 1 in 1700 births and the risk increases with maternal age. In such a situation, mental disabilities and some physical defects, most commonly heart anomalies, are observed. Life expectancy is approximately 60
years.
Trisomy 18 and 13 occur approximately once in 17,000 births, and the risk increases with maternal age. In such a case
mental disability and various physical defects are observed.
How long do you wait to get results?
Test results are usually ready within 2-3 weeks.
In approximately 5% of cases, the test does not give a result.
Interpretation of Results
After tests performed with cell-free DNA analysis in maternal blood, the fetus is diagnosed with trisomy 21 (Down
Syndrome), trisomy 18 and whether the patient is in a low or high risk group for trisomy 13
can be determined. Test results are never given as yes or no. This is because; The test has a 99% detection rate for the investigated trisomies and a 0.1% false positivity and 1% false negativity
rate. Since the test is applied within these reliability limits, it is currently accepted as a screening test, not a diagnosis
all over the world. Consequently; It is accepted that it is more accurate to give the analysis results as a risk calculation rather than a yes or no
form.
What are the Advantages of Harmony Prenatal Test?
1. Easy
No other procedure is required other than blood collection. It does not require a special form of transfer. It results within 2-3 weeks
.
2. Definitive
Other screening tests, such as blood tests performed in conjunction with ultrasound, have a 5% probability of false positive results (trisomy appearing as if there is
when it is not present) and 30% false negative result (trisomy being missed even though it is present).
available. In Harmony Prenatal Test, these rates are very low; It provides definitive results with less than 0.1% margin of error and 99% accuracy in detecting trisomy
21, which causes Down Syndrome.
3. Safe
Since only a blood sample is taken from the mother, it is a non-invasive procedure and does not pose any risk to the mother and the fetus. Although amniocentesis and Chorionic Villus Biopsy are widely used for diagnosis, they carry some risk for both mother and baby.
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