How does amniotic fluid dry up in the womb during pregnancy?

Decreases amniotic : Decreased amniotic fluid level most commonly occurs due to rupture of membranes. Other causes can be due placental insufficiency or fetal renal anomalies. Your baby will continue to normally produce amniotic fluid by voiding. So the amniotic fluid does not dry up. Either less fluid is produced or more fluid is leaving than is produced.