In the second trimester, which statement about maximum fetal size is true?

• A. There is a fixed gestational-age specific maximum in CRL.
• B. There is no fixed maximum; size increases with gestational age.
• C. Fetal size is capped at head circumference of 25 cm.
• D. Fetal size cannot exceed 30 cm in length.

Answer: (B)

In the second trimester, fetal growth progresses with gestational age and there isn’t a fixed maximum size. After the first trimester, we estimate growth using multiple ultrasound measurements (like head size, abdominal size, and limb length) that gradually increase as pregnancy advances. These measurements are interpreted against normative growth charts and show healthy, ongoing growth within a range of normal variation. There aren’t universal hard caps on size in this period; a fetus can be larger or smaller than average as long as the measurements stay within expected percentiles for the gestational age.