Polyhydramnios complicates between 0.13% to 3.5% of pregnancies with t
he cause remaining unknown in up to 66% of cases. Indomethacin is a pr
ostaglandin synthetase inhibitor presumed to affect the volume of amni
otic fluid through several mechanisms. Because treatment with indometh
acin during pregnancy is associated with serious fetal side effects a
strict therapeutic regimen should be adhered to at all times.