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Alpha-Fetoprotein or AFP test - Information on Reasons, Preparation, Method of testing and test results for Alpha-Fetoprotein or AFP

Alpha-Fetoprotein or AFP is a substance that is produced in the liver of the fetus. An alpha-fetoprotein test is done to detect the AFP levels in the blood of a pregnant woman. The content of alpha fetoprotein in the blood can be indicative of spina bifida or anencephaly, which are conditions that can affect the fetus. Usually, AFP is present in low levels in the blood of pregnant woman.

The level of alpha fetoprotein in the blood is used in a maternal serum triple screening test, which is used to determine the levels of AFP, an estrogen called unconjugated estriol and human chorionic gonadotropin. This helps to estimate the possibilities of certain birth defects that may develop in the baby.

Reasons for Performing the Alpha-Fetoprotein or AFP Test

An AFP test is done to detect problems of the brain and spine in the fetus, to check the fetus for down’s syndrome, to detect certain types of cancers such as that of the liver, ovaries or testicles, to check the progress of cancer treatment and to detect the presence of liver cancer in individuals with cirrhosis or hepatitis B.

Preparation for the Alpha-Fetoprotein or AFP Test

The individual does not have to prepare in any way before the test. If the individual is pregnant, then the body weight is recorded before the test since the results are based on body weight, in addition to race and the number of weeks of pregnancy that have passed.

Method of Testing Alpha-Fetoprotein or AFP

The alpha fetoprotein test is performed in the manner of a simple blood test and a blood sample is taken from the individual through insertion of a needle in the vein of the upper arm.

Test Results for Alpha-Fetoprotein or AFP

Normal AFP values can also vary depending on the age of the fetus. In some cases, a low or high value may indicate that the age of the fetus may have not been recorded correctly. As such an ultrasound may be used to determine the correct age.

High values of AFP can indicate that the woman may be carrying more than one fetus. It can also be indicative of neural tube defects in the fetus or that the abdominal organs or intestines are on the outside of the body, in which case surgery is required after birth, or that the fetus is not alive. In those who are not pregnant, high values could mean cancer of the ovaries, testicles or liver, cirrhosis, hepatitis or excessive alcohol consumption.

Low values of AFP could mean that the fetus is affected with down’s syndrome or that the age of the fetus is not correct. AFP is not present normally in those who are not pregnant.

Other Considerations for Alpha-Fetoprotein or AFP

The AFP test results may be affected if the woman is pregnant with more than one fetus, if the individual has gestational diabetes, if the individual smokes or if the individual has undergone a medical test that made use of radioactive tracers in the couple of weeks prior to the AFP test.