As we all know, the gender of the fetus has been determined as early as the early stages of pregnancy, but it only takes some time to confirm it with medical technology. The NT chart of boys and girls is very common in early pregnancy examinations of pregnant mothers. It can measure the thickness of the fetal neck of the pregnant mother through ultrasound imaging, and make a comprehensive judgment based on the mother\’s age, weight and other factors. to perform pregnancy check-ups