What defines polyhydramnios in terms of amniotic fluid index (AFI)?

Polyhydramnios is defined by an excess amount of amniotic fluid surrounding the fetus, and this condition is commonly categorized based on the Amniotic Fluid Index (AFI). The correct threshold for diagnosing polyhydramnios is an AFI of greater than or equal to 24 cm.

The AFI is determined by dividing the uterus into four quadrants and measuring the deepest pocket of fluid in each quadrant. The sums of these measurements give the total AFI. An AFI of 24 cm or more indicates a significant increase in amniotic fluid, which can be associated with various complications for both the mother and the fetus, such as fetal anomalies, gestational diabetes, and preterm labor.

The other numerical thresholds for AFI do not meet the established criteria for polyhydramnios, which is why they do not define the condition. The clinical significance of the AFI measurements ensures that the diagnosis is applied correctly, facilitating appropriate management and monitoring of pregnancies affected by this condition.