IUGR cannot be detected by USG using :

Ultrasound is the best method to diagnose IUGR not only to diagnose the growth restriction but also to identify a fetus of symmetrical or asymmetrical one. The biometric measures are: Biparietal diameter Head circumference Femur length Abdominal circumference Estimated fetal weight HC/AC and FL/AC ratio Above all AC is the single most sensitive parameter to detect IUGR. TEXT BOOK OF OBSTETRICS,Sheila Balakrishnan,2nd edition,page no.204,205.