The maximum depth of amniotic fluid is getting smaller and smaller belongs to the decrease of amniotic fluid, generally the depth of amniotic fluid between 3-8 centimeters is a normal phenomenon, if the depth of amniotic fluid is lower than 3 centimeters, it belongs to the abnormal situation. Depth of amniotic fluid is a professional medical term, which is the vertical depth of the maximum pool of amniotic fluid indicated by ultrasound, and is an important indicator for determining how much amniotic fluid is present. In general, the depth of amniotic fluid in 3-8 cm is the normal amount of amniotic fluid, the depth of amniotic fluid is not a fixed value, there are high and low is very normal, if the maximum depth of amniotic fluid is getting smaller and smaller, but fluctuations in this range, are normal. If the depth of amniotic fluid decreases gradually and is less than 3 cm, it is called amniotic fluid hyponatremia, which is an abnormal phenomenon and may cause fetal distress, hypoxia and other symptoms. If the amniotic fluid is too low in early pregnancy, it will lead to limb shortage, and if the amniotic fluid is too low in late pregnancy, it will lead to skeletal and muscular deformities, stillbirth and other situations. It is recommended that pregnant women pay attention to rest, always observe the fetal movement, carry out obstetric examination on time, and if there is any abnormality, consult a doctor in time, and if necessary, choose to terminate the pregnancy.