alpha-fetoprotein

n. (Medicine) AFP, protein produced by a fetus during development and is found in amniotic fluid and the mother's bloodstream; protein produced by the liver cells; protein found in the flow of blood of men suffering from non seminomatous testicular cancer

Alpha-fetoprotein (AFP) is a molecule produced in the developing embryo and fetus. In humans, AFP levels decrease gradually after birth, reaching adult levels by 8 to 12 months. Normal adult AFP levels are low, but detectable; however, AFP has no known function in normal adults. In normal fetuses, AFP binds the hormone estradiol. AFP is measured in pregnant women, using maternal blood or amniotic fluid, as a screening test for a subset developmental abnormalities, principally open neural tube defects. It is also measured in pregnant women, other adults, and children, to detect a subset tumors, principally hepatocellular carcinoma and endodermal sinus tumors.
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noun
protein found in the amniotic fluid when the fetus has an open neurological deficiency such as meningomyelocele

[AL-fa-FEE-toe-PRO-teen]
AFP. A protein normally produced by a fetus. AFP levels are usually undetectable in the blood of healthy adult men or women (who are not pregnant). An elevated level of AFP suggests the presence of either a primary liver cancer or germ cell tumor.