Polyhydramnios is a condition in which there is an abnormally large amount of amniotic fluid surrounding the fetus. It is typically defined as an amniotic fluid index (AFI) greater than 24 centimeters or a single deepest pocket exceeding 8 centimeters. Mild polyhydramnios is relatively common and often idiopathic (no identifiable cause), but moderate to severe cases may be associated with fetal conditions such as gastrointestinal obstruction (preventing the fetus from swallowing fluid), neural tube defects, chromosomal abnormalities, or maternal diabetes. Excessive fluid can lead to preterm labor, premature rupture of membranes, and umbilical cord prolapse. Ultrasound is the standard method for detecting and quantifying amniotic fluid volume, and the finding of polyhydramnios prompts further investigation into potential underlying causes.
Sonography Term