<div style="color: blue;"> <span style="font-size: large;">Idiopathic polyhydramnios</span></div>

In approximately 60% of cases of polyhydramnios, there are no abnormalities detectable in either the mother or the fetus.

Polyhydramnios. Sonogram of a fetus (F) with excessive amniotic fluid and a floating extremity (arrow). (P, placenta.)