Reduced AFP

Human α-fetoprotein (AFP) is a tumour-associated foetal mammalian glycoprotein involved in ontogenic and oncogenic growth. (1)

In the clinical laboratory, AFP has been employed both as a post-operational tumour marker and as a gestational age-dependent foetal defect marker, demonstrating utility in screening for neural tube defects and aneuploidies. (2)

When a foetus has neural tube defects, maternal serum AFP levels are elevated, whereas chromosomal disorders are associated with lower levels. Amniocentesis is needed to assay AFP levels in the amniotic fluid.

The following factors may contribute to low levels of maternal serum AFP:

• Down syndrome
• Increased maternal weight
• Foetal death
• Hydatidiform mole
• Trisomy 18, also known as Edwards syndrome
• Incorrect gestational age (older than calculated)

Reference

1. Pak VN. The use of alpha-fetoprotein for the treatment of autoimmune diseases and cancer. Ther Deliv. 2018 Jan;9(1):37-46.
2. Sharony R et al. Is the ratio of maternal serum to amniotic fluid AFP superior to serum levels as a predictor of pregnancy complications? Arch Gynecol Obstet. 2016 Apr;293(4):767-70