The NT test determines the possibility of Down’s syndrome by checking the thickness of the posterior nuchal translucency layer of the fetus. The NT test is usually performed at 11-13 weeks +6 days of gestation to check the thickness of the nuchal translucency layer to determine whether the fetus has abnormal development. The thicker the nuchal translucency layer, the higher the probability of fetal developmental abnormalities, indicating that the fetus has chromosomal abnormalities and is more likely to have Down’s syndrome, which requires further non-invasive DNA testing or amniocentesis under the guidance of a doctor to confirm the diagnosis, and then take appropriate treatment measures according to the fetal development. To avoid abnormal fetal development during pregnancy, it is recommended that pregnant women pay attention to their diet, consume fresh fruits and vegetables rich in vitamins, as well as meat and egg dairy products, and have regular checkups and seek medical attention when they are unwell.