Alpha fetoprotein (AFP) is a protein produced by the liver and yolk sac of a developing baby during pregnancy. AFP levels go down soon after birth. It is likely that AFP has no normal function in adults.
A test can be done to measure the amount of AFP in your blood.
Fetal alpha globulin; AFP
How the Test is Performed
A blood sample is needed. Most of the time, blood is typically
How to Prepare for the Test
You do not need to take any special steps to prepare.
How the Test will Feel
You may feel slight pain or a sting when the needle is inserted. You may also feel some throbbing at the site after the blood is drawn.
Why the Test is Performed
Your health care provider may order this test to:
- Screen for problems in the baby during pregnancy. (The test is done as part of a larger set of blood tests called
- Diagnose certain liver disorders.
- Screen for and monitor some cancers.
The normal values in males or nonpregnant females is generally less than 40 micrograms/liter.
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Greater than normal levels of AFP may be due to:
Cancerin testes, ovaries, biliary (liver secretion) tract, stomach, or pancreas Cirrhosis of the liver Liver cancer Malignant teratoma Recovery from hepatitis
- Problems during pregnancy
Driscoll DA, Simpson JL, Holzgreve W, Otano L. Genetic screening and prenatal genetic disgnosis. In: Gabbe SG, Niebyl JR, Simpson JL, et al, eds. Obstetrics: Normal and Problem Pregnancies. 7th ed. Philadelphia, PA: Elsevier; 2017:chap 10.
Fundora J. Neonatology. In: Hughes HK, Kahl LK, eds. The Johns Hopkins Hospital: The Harriet Lane Handbook. 21st ed. Philadelphia, PA: Elsevier; 2018:chap 18.
Wapner RJ. Prenatal diagnosis of congenital disorders. In: Creasy RK, Resnik R, Iams JD, Lockwood CJ, Moore TR, Greene MF, eds. Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice. 7th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 30.
Review Date: 26/08/2017
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright ©2019 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.
Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Health. Please discuss with your doctor any questions or concerns you may have.