Alpha-fetoprotein is a serum protein found in all mammalian species during embryonic development. This glycoprotein is produced by the fetal liver and yolk sac during the first trimester of pregnancy. AFP levels are analysed through maternal blood or the amniotic fluid to detect any abnormality in the developing fetus. It also acts as a tumor marker and hence is an important marker for the management of cancers. Serum AFP is elevated in people with certain tumors. AFP is used as a control and calibrator in various in vitro diagnostic testing kits.