During pregnancy, it is of great significance for pregnant women to go to the hospital for B-ultrasound examination. B-ultrasound during pregnancy can monitor the growth and development of the fetus and reduce the birth rate of children with malformations and defects. So, during the entire pregnancy, how many B-ultrasound examinations are best for pregnant women? Next, we will analyze it for us. Experts point out that it is of great significance for pregnant women to have B-ultrasounds, but it does not mean that the more they are done, the better. Ultrasound is a physical factor, a type of energy. In the early stages of pregnancy, if a pregnant woman has too many B-ultrasound examinations, she may