“NT is the thickness of the fetal nuchal translucency, an important indicator of early Down’s syndrome screening, and is used to determine the thickness of the fluid layer in the subcutaneous tissue of the fetal nuchal area to assess the risk of Down’s syndrome and congenital heart disease. However, the NT test is measured by ultrasound, during which the development of other parts of the fetus is observed. “If the nasal bone is visible, the nasal bone is seen during the ultrasound and this alone is a normal result. As to whether the NT test result is normal or not, it should be analyzed together with the NT test measurement.