NT value of 5mm, everything else is normal is also a problem. NT refers to the thickness of fetal nuchal translucency measured by ultrasound, and the normal value is less than 3mm. Fetal nuchal translucency of 5mm is abnormal, and it is recommended to perform further tests, such as non-invasive DNA, amniocentesis, and so on. Based on the value of nuchal translucency, it can be roughly estimated that the fetus has Down syndrome and other chromosomal disorders. The normal value of nuchal translucency is less than 3mm, and if the value is greater than 3mm, further tests are required. Karyotyping and amniocentesis are the gold standard for definitive diagnosis of fetal chromosomal abnormalities, whereas non-invasive DNA, although less invasive, is only a screening test, not a definitive diagnosis. If the thickness of the fetal nuchal translucency is 5mm, chromosomal karyotyping, amniocentesis, and non-invasive DNA are recommended, and the decision to terminate the pregnancy will be made based on the specific results.