Fetal growth abnormally resulting in a proportionally small fetus is referred to as?

• A. Symmetric IUGR
• B. Asymmetric IUGR
• C. Macrosomia
• D. Post-term pregnancy

Answer: (A)

Symmetric intrauterine growth restriction describes a fetus that is small in all dimensions, so biometric measurements are reduced by about the same percentage. This points to an insult affecting the fetus early in development, such as chromosomal abnormalities, congenital infections, or other early problems. On ultrasound, head measurements (like head circumference) and body measurements (such as abdominal circumference and femur length) are all proportionally reduced, so the head-to-abdomen ratio remains roughly normal.

This differs from an asymmetric pattern, where growth restriction happens later in pregnancy and the abdomen is notably smaller than the head because placental insufficiency affects body growth more than early brain growth. Macrosomia refers to a fetus that is large for gestational age, and post-term pregnancy describes gestation extending beyond the expected due date, not a growth pattern.