|Procedure: Alpha-Fetoprotein Test|
Description and Purpose
Alpha-Fetoprotein (AFP) or foetal
alpha globulin , released by the baby's liver, is present in the
mother's blood. Abnormally high AFP levels may signal abnormalities including
neural tube defects (such as spina bifida), kidney problems, malformations
of the digestive tract, threatened ,
or death of the foetus. Abnormally low AFP levels may indicate , but this diagnosis must be confirmed by other tests.
Preparation and Procedure
The test is usually performed between the 15th and 18th weeks of pregnancy
and is performed on a blood sample. Sometimes the AFP test can be combined
with an analysis for (hCG) and unconjugated estriol. This is termed triple
screening . All 3 substances, which are produced by the foetus and
enter the mother's blood stream, indicate an increased risk for Down syndrome,
spina bifida, and other significant , and of and other third-trimester complications.
It should be noted that these tests can't be used to diagnose these conditions,
but helps identify foetuses of younger women at risk and, thus, indicates
if more definitive testing, such as
or , is necessary.
The information in this page is presented in summarised form and has been taken
from the following source(s):
The Yale University School of Medicine Patient's Guide to
Medical Tests, Barry L. Zaret M.D., Senior Editor, published by Houghton Mifflin.
(def;articles & more)