Alpha-Fetoprotein (AFP) screening is a kind of blood test performed to detect chromosomal abnormalities in a fetus during the second trimester of pregnancy. It is a part of the triple test or Bart's test or Kettering test. AFP is released by the yolk sac, liver, and GI tract of unborn so the level is high in pregnant woman but it may also be present in non-pregnant persons. AFP test can be done on maternal serum (blood plasma). Instead of being diagnostic AFP serum test is determintal in nature. The sensitivity of this plasma protein poses alert for many diseases in baby and adults.