The amount of amniotic fluid is greatest at about 34 weeks (gestation) into the pregnancy, when it averages 800 mL. About 600 mL of amniotic fluid surrounds the baby at full term (40 weeks gestation). The amniotic fluid constantly moves (circulates) as the baby swallows and "inhales" the fluid, and then releases it.

Why does amniotic fluid decrease at term?

Various factors can contribute to low amniotic fluid in pregnancy, including: Your water breaking. The placenta peeling away from the inner wall of the uterus — either partially or completely — before delivery (placental abruption) Certain health conditions in the mother, such as chronic high blood pressure.

What is the normal level of amniotic fluid at 32 weeks?

Amniotic fluid levels vary throughout the different stages of pregnancy. During weeks 32–34, the amniotic fluid volume may increase to 800 milliliters (ml) or more. From 34 weeks through to labor, the fluid decreases to about 400 ml .