DOUBLE SCREENING TEST FOR WHAT?

DURING PREGNANCY (in pregnancy) DOUBLE TEST WHAT?
Bilateral screening in pregnancy, the baby is a test that can be done to investigate some of the chromosomal abnormalities. According trisomy 21 babies dual test results (Down syndrome) and trisomy 18 (Edwards syndrome) called the risk of chromosomal abnormalities in the baby investigated. These diseases are diseases with mental retardation and some organ abnormalities. This is why it's called intelligence test test to this is also double test is not a test that measures the baby's intelligence level.

between 11-14 weeks of pregnancy for the double test of blood is taken from the mother (as received in the same regular blood tests). This blood β-hCG and PAPP-A levels were measured, the mother's age and other characteristics of the formula is determined by means of computer results. This test, called a binary test. If this formula to the baby's nuchal translucency (NT) is also added to the rate becomes clearer accuracy of the results obtained, this test combined test (duo combined test) is called. So the combined test is a test conducted as a result of the combined thickness of the neck with a double test. Down syndrome screening test detected 65% of the bilateral baby it can be applied, with 85% of the combined test can be determined. Both tests can not detect all of Down syndrome babies, babies with Down syndrome in a number of high-risk pregnancies will come as a result of this test it is a normal future.

As a result of this double test for chromosomal abnormalities that can not be determined definitively whether the baby has not only higher than normal risk of these abnormalities in the baby is taken to answer the question. If the risk is high if these anomalies in the baby's normal to get a definitive answer to the question Is there a CVS or amniocentesis methods are applied.

Risk identification according to binary test results:
high risk for Down sensro my limit 1/270 in binary test results are accepted. That results; 1/270 if greater than (for example, 1/200) the risk of Down syndrome babies are higher than normal but the baby may be normal. CVS or amniocentesis should be done for a definitive diagnosis.
Binary test results, Edwards syndrome (trisomy 18) for high-risk limits 1/100 accepted. So the result 1 / 100th of the great inference (eg 1/80) the risk of Edwards syndrome in infants is higher than normal, but the baby may be normal. CVS or amniocentesis should be done for a definitive diagnosis.

Nasal bone measurement (nasal bone):
Absence of nasal bone (nasal bone absence), it is more accurate to describe, because the presence or absence of bone is evaluated. Nasal bone so there are some centers by evaluating the combined bilateral değenlendiril ultrasound test of the nasal bone. Nasal bone can not be seen on ultrasound increases the risk of trisomy. Because the nasal bone can be seen in 98% of normal fetuses between 11-14 weeks, it can not be seen only in 2%. of fetuses with trisomy 21 the nasal bone is not visible at 70%. 50% of fetuses with trisomy 18 the nasal bone is not visible. 30% of fetuses with trisomy 13 the nasal bone is not visible.