What is the reason for low amniotic fluid? Amniotic fluid is an important protective substance needed by the fetus to grow and develop in the womb. It not only provides nutrition, but also protects the fetus from impact and stabilizes the fetus\’ body temperature. The normal amount of amniotic fluid should be between 500-1000 ml. Once too little amniotic fluid occurs, it will have adverse effects on the growth and development of the fetus. So, what is the reason for low amniotic fluid? 1. Physiological amniotic fluid