The term macrosomia is not clinically accurate, but rather a folk name for a pregnancy that includes several programs, and 4D ultrasound is one of the fetal screening tests during pregnancy. During pregnancy, there are three more important screening programs, including NT examination, Down screening examination, 3D/4D ultrasound examination. 1. NT test: When the pregnancy is within 11-13 weeks, the thickness of the fetal nuchal translucency band is measured by ultrasound to initially diagnose the chance of the fetus having Down syndrome. If the thickness of the nuchal translucency is more than 2.5mm, non-invasive DNA or amniocentesis should be performed according to the situation. 2. Down’s syndrome screening: divided into early Down’s syndrome screening and intermediate Down’s syndrome screening, i.e. serological screening, once the serological screening result is high-risk or critical risk line, it is necessary to do non-invasive DNA or amniocentesis in time to rule out chromosomal abnormality in the fetus. 3. 3D/4D ultrasound: around 22-26 weeks of pregnancy is the best time to do 3D/4D ultrasound, which can see fetal surface malformations, limb malformations, visceral malformations and so on. All three of these types of detector tests are very important, so it is important to do all of the tests under your doctor’s guidance after you become pregnant.