Fetoprotein, alpha- (AFP)


Fetoprotein, alpha- (AFP): Alpha fetoprotein is a plasma protein that is normally produced by the fetus. It serves as the basis for some valuable tests.

Alpha fetoprotein is manufactured principally in the fetus’s liver and gastrointestinal (GI) tract besides the yolk sac, a structure temporarily present during embryonic development.

The alpha fetoprotein level is typically high in the fetus’s blood. It decreases in the baby’s blood after birth. And by one year of age, it is virtually undetectable.

During pregnancy, alpha fetoprotein crosses the placenta from the fetal circulation and appears in the mother’s blood. The AFP level in the mother’s blood (the maternal serum alpha fetoprotein) provides a screening test for several disorders including:

Open neural tube defects (anencephaly and spina bifida); and
Down syndrome (and other chromosome abnormalities).

The maternal serum alpha fetoprotein (MSAFP) tends to be:

High with open neural tube defects such as anencephaly and spina bifida (meningomyelocele); and
Low with Down syndrome (trisomy 21, an extra chromosome number 21).

Alpha fetoprotein production is essentially zero after a year of age. However, it increases again under the stimulus of some liver diseases. It may, for example, be produced by viral hepatitis and cirrhosis of the liver. Alpha fetoprotein is also made by primary liver tumors (hepatomas) and by germ cell tumors (teratocarcinoma and embryonal cell carcinomas). A person’s serum alpha fetoprotein level can therefore be used to help detect these conditions and monitor their treatment.

Read Also:

  • Fetoscope

    Fetoscope: A device used to obtain information about a fetus within the uterus. There are two types of fetoscopes: A fiberoptic scope for looking directly at the fetus within the uterus and a stethoscope designed for listening to the fetal heart beat.

  • Fetoscopy

    Fetoscopy: Examination of a fetus within the uterus by using a fetoscope.

  • Fetus

    Fetus: An unborn offspring, from the embryo stage (the end of the eighth week after conception, when the major structures have formed) until birth.

  • FEV1

    FEV1: Forced Expiratory Volume in the first second. The volume of air that can be forced out in one second after taking a deep breath, an important measure of pulmonary function.

  • Fever

    rising body temperatures apparently are capable of killing off many disease- producing organisms. For that reason, low fevers should normally go untreated, although you may need to see your doctor to be sure if the fever is accompanied by any other troubling symptoms. As fevers range to 104 F and above, however, there can be […]


Disclaimer: Fetoprotein, alpha- (AFP) definition / meaning should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. All content on this website is for informational purposes only.