Will a B-ultrasound done by pregnant women harm the fetus?

　　B-ultrasound can cause harm to pregnant women fetus ? ? In foreign countries, B-ultrasound doctors are given special allowances because rays can cause more or less damage to the body. The "hidden rule" for pregnant mothers in China is usually to have a B-ultrasound examination every month after 3 months.

　　However, in baby of nerve During the developmental period, any small impact may cause harm to his future. So my suggestion is, during pregnancy female The number of B-ultrasound examinations should not exceed 3 times, and it is best to conduct them after 6 months. >>> What should pregnant women eat that can cause miscarriage?