Which list includes all four biometric measurements used in fetal dating?

Which list includes all four biometric measurements used in fetal dating?

• A. BPD, HC, AC
• B. BPD, HC, AC, FL
• C. HC, AC, FL
• D. BPD, AC, FL

Answer: (B)

The main concept is that fetal dating in mid to late pregnancy relies on a standard set of biometric measurements: biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL). Each measurement captures a different aspect of fetal growth—the head dimensions (BPD and HC) reflect skull and brain development, AC tracks overall fetal abdominal growth, and FL represents limb length. Using all four together provides a more accurate estimation of gestational age than any subset, because they balance growth variations in different body parts. The option that includes BPD, HC, AC, and FL is the complete and best choice for dating. Lists missing any one of these measurements would be incomplete for comprehensive dating. Note that crown-rump length is used for dating in the first trimester, not in this mid-to-late-pregnancy set.

The main concept is that fetal dating in mid to late pregnancy relies on a standard set of biometric measurements: biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL). Each measurement captures a different aspect of fetal growth—the head dimensions (BPD and HC) reflect skull and brain development, AC tracks overall fetal abdominal growth, and FL represents limb length. Using all four together provides a more accurate estimation of gestational age than any subset, because they balance growth variations in different body parts. The option that includes BPD, HC, AC, and FL is the complete and best choice for dating. Lists missing any one of these measurements would be incomplete for comprehensive dating. Note that crown-rump length is used for dating in the first trimester, not in this mid-to-late-pregnancy set.