Alpha-Fetoprotein test (AFP)
Description
Physicians perform the test by removing a sample of the mother’s blood, usually at between 15 and 20 weeks and sending it to a laboratory to test for the presence of the AFP protein. A fetus normally has this protein present in its body, and a tiny amount of it normally migrates across the placenta and through the amniotic fluid into a mother’s blood stream. In conditions like spina bifida and anencephaly, larger amounts of AFP find their way into the mother’s blood stream. Not all fetuses with one of these disorders will leak a detectable amount of AFP; conversely, not all mothers with elevated AFP have fetuses with either condition. The test is simply a screening, test, and is often analyzed alongside other tests to ascertain the risk for genetic abnormality in the fetus.
For more information on blood tests in general, click here.
Last updated: 08-Jun-01
Related Conditions:
Pregnancy
