Summary: During pregnancy, we need to do many examinations, the three most important of which are: 4D color ultrasound, Tang screening examination and sugar screening examination. Among these three examinations, we all know the four-dimensional examination and the Tang screening examination. The first is to rule out abnormalities, and the second is to screen pregnant mothers for gestational diabetes. Do you know about Tang screening test? During pregnancy, we need to do many examinations, the three most important of which are: four-dimensional color ultrasound examination, Tang screening examination and sugar screening examination. Among these three examinations, we all know the four-dimensional examination and the Tang screening examination. One is to exclude abnormalities, and the other is to screen