The Transverse Cerebellar Diameter Resists IUGR

When monitoring a fetus with suspected intrauterine growth restriction (IUGR) and unknown menstrual dates, traditional biometry (like the abdominal circumference) is unreliable for establishing gestational age because it is rapidly affected by placental insufficiency.

The transverse cerebellar diameter (TCD) is unique because it is the single biometric variable least affected by growth restriction.

Clinical Bottom Line: Use the transverse cerebellar diameter as an independent, reliable reference marker to estimate gestational age in a growth-restricted fetus.