In the case of low amniotic fluid 4D can not be done firstly need to make up the amniotic fluid, or through the way of amniocentesis for examination. 4D ultrasound is a test to rule out fetal malformations. The development of the fetal head and heart can be screened by 4D ultrasound around 25 weeks of pregnancy. Since everyone is different, the normal value of amniotic fluid is only an approximate range number and cannot be generalized. If the amount of amniotic fluid is particularly low, it will not be particularly clear when distinguishing the fetal limbs and organ patterns. The first thing you can do is to drink a lot of water in the near future, and you can also take fluids to replenish the amniotic fluid under the advice of your doctor. If this does not help, amniocentesis can be performed on the advice of your doctor. Amniocentesis is done to find out the cause of low amniotic fluid and to rule out fetal abnormalities. After the puncture, you should rest in bed and avoid sexual intercourse. If you have abdominal pain or vaginal bleeding, go to a regular hospital for treatment.