How do you see four-dimensional data?

The four-dimensional color Doppler examination report often has some tips, whether the baby development is normal indicators, biparietal diameter, head circumference, femoral length, abdominal circumference, lateral ventricle width, amniotic fluid index, fetal heart rate, etc., these development indicators commonly used data. 1, normal fetal heart rate between 120-160 beats/min, more than this range is abnormal. Biparietal diameter and femoral length, generally increase with the increase of gestational weeks. 2, most of the baby's femur length is 20-30mm less than the biparietal diameter, more than this range is abnormal. 3, the width of the baby's lateral ventricle can not exceed 10mm, more than 10mm is abnormal. 4, amniotic fluid depth between 3-8cm; amniotic fluid index between 8-18cm, more than this range is abnormal.