During which gestational weeks are AFP values highest?

During which gestational weeks are AFP values highest?

• A. 6th to 14th weeks
• B. 2nd to 3rd weeks
• C. 20th to 24th weeks
• D. 28th to 32nd weeks

Answer: (A)

Alpha-fetoprotein (AFP) levels rise early in pregnancy as the fetus produces AFP in the yolk sac and fetal liver, and they reach their highest concentrations during the mid-first trimester to early second trimester. This window—roughly between six and fourteen weeks—reflects the peak fetal production before the pattern shifts as organs mature and clearance mechanisms change. After this period, AFP production relative to what’s measured in maternal serum declines, so later weeks show lower values. The other time frames are away from the peak production period, either earlier when production hasn’t ramped up yet or later when levels have begun to fall.

Alpha-fetoprotein (AFP) levels rise early in pregnancy as the fetus produces AFP in the yolk sac and fetal liver, and they reach their highest concentrations during the mid-first trimester to early second trimester. This window—roughly between six and fourteen weeks—reflects the peak fetal production before the pattern shifts as organs mature and clearance mechanisms change. After this period, AFP production relative to what’s measured in maternal serum declines, so later weeks show lower values. The other time frames are away from the peak production period, either earlier when production hasn’t ramped up yet or later when levels have begun to fall.