Decreased MSAFP levels are associated with which condition?

Decreased MSAFP levels are associated with which condition?

• A. Down syndrome
• B. Open neural tube defects
• C. Abdominal wall defects
• D. Post-term pregnancy

Answer: (A)

MSAFP testing uses the level of fetal AFP in maternal blood to screen for fetal conditions. AFP is produced by the fetus, and levels can rise in the mother’s blood when there are open defects like neural tube or abdominal wall defects, because AFP leaks into the amniotic fluid and then into maternal circulation. However, when there are chromosomal abnormalities such as Down syndrome, AFP production or transfer patterns are reduced, leading to lower maternal serum AFP levels. Therefore decreased MSAFP is associated with Down syndrome. Open neural tube defects or abdominal wall defects typically cause increased AFP, not decreased, and post-term pregnancy does not have a specific decreased AFP association.

MSAFP testing uses the level of fetal AFP in maternal blood to screen for fetal conditions. AFP is produced by the fetus, and levels can rise in the mother’s blood when there are open defects like neural tube or abdominal wall defects, because AFP leaks into the amniotic fluid and then into maternal circulation. However, when there are chromosomal abnormalities such as Down syndrome, AFP production or transfer patterns are reduced, leading to lower maternal serum AFP levels. Therefore decreased MSAFP is associated with Down syndrome. Open neural tube defects or abdominal wall defects typically cause increased AFP, not decreased, and post-term pregnancy does not have a specific decreased AFP association.