Definition of Fibrinogen:

Fibrinogen is a protein produced by the liver. This protein helps stop bleeding by helping blood clots to form. A blood test can be done to tell how much fibrinogen you have in the blood.

How the test is performed:

A blood sample is needed. For information on how this is done, see: Venipuncture

How to prepare for the test:

There is no special preparation needed.

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 if you have problems with blood clotting, especially if you have excessive bleeding.

Normal Values:

The normal range is 200 - 400 milligrams per deciliter (mg/dL).

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

The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.

What abnormal results mean:

Abnormal results may be due to:

• Excessive fibrinogen use (as in disseminated intravascular coagulation)
• Fibrinogen deficiency (from birth, or acquired after birth)
• Fibrinolysis
• Hemorrhage

The test may also be performed for placenta abruptio.

What the risks are:

There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight but may include:

• Excessive bleeding
• Fainting or feeling light-headed
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)

Note: This test is most often performed on people who have bleeding disorders. The risk of excessive bleeding is slightly greater in such people than for those who do not have bleeding problems.