NT is an abdominal ultrasound test that is performed to preliminarily rule out the risk of chromosomal disorders in the fetus, and should be performed on time as prescribed by the doctor. NT test, that is, fetal nuchal translucency thickness measurement, is an abdominal ultrasound examination performed at 11-13+6 weeks of gestation to initially screen the risk of chromosomal disorders in the fetus, and should be operated by a specialized doctor. The normal value is <2.5mm. When the NT measurement is negative, it is important to follow the doctor’s instructions to continue with the labor and delivery on time, and also to carry out the next step of screening for abnormalities, such as Down’s syndrome. When the NT positive results, can only indicate that the fetus has an elevated risk of chromosomal disorders, but not a definitive diagnosis, you need to follow the doctor’s instructions for prenatal diagnosis and genetic counseling, and based on the results to determine the next step in the treatment plan.