The abdominal circumference is roughly an ellipse, and the circumference can be estimated if the orthogonal diameters are known
Level of measurement: stomach and umbilical vein-ductus venosus complex
(1) transverse abdominal diameter in cm (TAD)
(2) anteroposterior abdominal diameter in cm (APAD)
abdominal circumference in cm =
= PI() * 0.5 * ((TAD) + (APAD))
To read more or access our algorithms and calculators, please log in or register.
Specialty: Obstetrics & Gynecology