To have a healthy baby, pregnant women need to frequently go to the hospital for prenatal check ups during pregnancy. For example, NT examination is a very important screening test. If the NT examination fails, it may indicate that there are problems with the fetal development. Non invasive DNA can be used for re examination. When should a high NT value be considered for non-invasive testing?
NT examination is performed around 12 weeks of pregnancy. If there are any abnormalities in the examination results, do not terminate the pregnancy blindly. You can wait for another two weeks and undergo non-invasive re examination. Non invasive actually refers to non-invasive DNA testing. The best time for this test is between 14-18 weeks of pregnancy, during which the accuracy of the test is higher and the results are more valuable for reference.
In fact, both NT and non-invasive DNA belong to screening tests, but there are certain differences in the operation methods and accuracy between these two tests. NT examination is conducted through blood testing, and the normal value cannot exceed 3, otherwise it indicates abnormal fetal development and may have Down syndrome. Non invasive DNA testing is conducted through blood sampling, with higher accuracy than nt.
In addition to NT and non-invasive DNA, amniocentesis is also a type of examination for screening Down syndrome and has the highest accuracy rate. However, the operation method of amniocentesis is relatively complex and carries high risks, which may lead to miscarriage. Therefore, it is recommended that pregnant women choose this examination method with caution.
