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Vitamin K-dependent clotting factor (Factor VII) activity in serum

Published: August 9, 2026Updated: August 16, 2026

This test measures the activity level of Factor VII, a protein essential for blood clotting. It helps assess how well your blood can clot in response to injury.

Quick summary

["Factor VII activity helps identify bleeding disorders or clotting issues linked to vitamin K deficiency or liver problems."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
53860-3
Short code
VLCFA C24:0 SerPl-mCnc
Synonyms
VLCFA C24:0 SerPl-mCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your doctor may order this test if you have symptoms of bleeding problems, such as easy bruising, excessive bleeding from cuts, or unexplained nosebleeds. It may also be used to monitor treatment for conditions like liver disease or vitamin K deficiency that affect clotting.

What to Expect Before the Test

No special preparation is needed. You may have a small needle inserted into your arm to draw blood. If you’re on blood-thinning medications, let your doctor know before the test.

What the Results Mean

Results are compared to a standard range for healthy individuals. Low levels may indicate bleeding disorders, liver disease, or vitamin K deficiency, while very high levels could suggest rare clotting disorders.

Common Conditions Monitored

This test is often used to diagnose or monitor bleeding disorders, liver disease, or vitamin K deficiency. It may also be part of a broader evaluation for patients on anticoagulant therapy.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Factor VII plays a critical role in the blood clotting cascade. Low activity can lead to increased bleeding risk, while elevated levels may rarely suggest inherited clotting disorders or certain medications.

Short name

Factor VII Activity (Serum)

Frequently asked questions

What causes low Factor VII activity?
Low Factor VII activity can result from liver disease, vitamin K deficiency (due to poor diet, medications like antibiotics, or malabsorption), or inherited bleeding disorders. It may also appear in people on blood-thinning medications.
How long does it take to get results?
Results are typically available within 1 to 3 business days, depending on your lab’s processing time. Your doctor will discuss the findings with you.
Can diet affect Factor VII levels?
Yes, vitamin K-rich foods (like leafy greens, broccoli, and some fortified foods) can influence Factor VII activity. If you’re on vitamin K supplements or have dietary restrictions, discuss them with your doctor before testing.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy