In general, if the NT test result is normal, the probability of pregnant women having Down’s syndrome children is relatively low, but the possibility of having Down’s syndrome children can not be completely ruled out, and it is best to carry out Down’s syndrome screening for further testing, which is more accurate.NT test is an important indicator of the presence of chromosomal or structural malformations of a fetus, which can be measured by ultrasound in terms of the thickness of the skin folds in the nape of the neck.NT test is accurate, but it is affected by many factors such as the position of the testing instrument and the size of the fetus. The NT test has a certain degree of accuracy, but the NT test is affected by many factors such as the testing instrument, fetal position, fetal size and gestational week, so a normal test result does not mean that the fetus is normal. Therefore, if you are not sure about the test results or if the test results show a critical risk, it is best to go through further tests such as Down’s syndrome screening, non-invasive DNA testing, amniocentesis, etc. under the guidance of a doctor for a clear diagnosis. In addition, in order to avoid the birth of a child with Down’s syndrome, pregnant women need to ensure adequate sleep and rest time, avoid exposure to radiation, toxic and harmful substances and other adverse environments during the early stages of pregnancy, and undergo regular obstetric examinations. If abnormalities of the fetus are detected, complete the relevant examinations as early as possible, and treat the symptoms according to the situation.