Do you need to do four-dimensional ultrasound after doing system B ultrasound?

If the system B ultrasound check normal fetal development does not need to further check the four-dimensional color ultrasound. Because the system B ultrasound in pregnancy is known as a large row abnormal check, this check authority is relatively high, if the system B ultrasound clearance means that more than 90% of the child is healthy. Relative to the four-dimensional color ultrasound system B ultrasound radiation is smaller and safer, so there is no need to further check. In addition to system B ultrasound, expectant mothers should do Down's screening or non-invasive DNA. System B ultrasound can only rule out structural abnormalities in the fetus, but whether the chromosomes are normal requires blood tests or examination of amniotic fluid puncture, etc. can be judged.