Alpha fetoprotein Health Article

Licensed from

Table of Contents

Definition Alternative Names How the test is performed How to prepare for the test How the test will feel Why the test is performed Normal Values What abnormal results mean What the risks are References

Reviewer Info: Linda Vorvick, MD, Seattle Site Coordinator, Lecturer, Pathophysiology, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; and Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.; ADAM Health Illustrated Encyclopedia, 10/28/2008

Page: 1 2 Next >

Definition

Alpha fetoprotein (AFP) is a protein normally produced by the liver and yolk sac of a fetus. AFP levels decrease soon after birth. AFP probably has no normal function in adults.

A test can be done to measure the amount of AFP in your blood.

Alternative Names

Fetal alpha globulin; AFP

How the test is performed

Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.

Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.

Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.

How to prepare for the test

There is no special preparation.

How the test will feel

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed

Your doctor may order this test to:

Screen for problems in the fetus during pregnancy
Diagnose certain liver disorders
Screen for and monitor some cancers

During pregnancy, this AFP test can be done along with the examination of amniotic fluid (amniocentesis) to help detect fetal spina bifida or other birth defects.

Normal Values

The normal values in males or nonpregnant females is generally less than 40 micrograms/liter.

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

Page: 1 2 Next >

Blood test

Use of this Web site constitutes acceptance of our Terms and Conditions of Use and Privacy Policy.