If the amniotic fluid index is less than 5 cm and the dark area of amniotic fluid is less than 2 cm, the amniotic fluid is too small. In this case, ultrasound should be done first to rule out abnormalities of fetal development. If the fetus has abnormalities, the pregnancy should be terminated as soon as possible, and the choice of ultrasound-guided, transabdominal amniotic cavity injection of estradiol to induce labor. If the fetal development is normal and the amniotic fluid is too low, we should look for the cause, increase the amount of rehydration, improve the placental function, anti-infection, and ask the pregnant woman to count the fetal movement by herself and perform fetal biophysical scoring. ultrasound dynamically monitors the amniotic fluid volume and the ratio of the highest systolic blood flow velocity to the lowest diastolic blood flow velocity of the umbilical artery, and closely monitors the intrauterine condition of the fetus. For a fetus that is full term and has low amniotic fluid, the pregnancy can be actively terminated. If it is more than 7 months, more amniotic fluid volume, umbilical cord treatment, prolonged gestational weeks, and also the amniotic cavity perfusion fluid method should be used.