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Cytomegalovirus (CMV) Antibody, IgG, Serum

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

This test measures your body’s immune response to the cytomegalovirus (CMV), a common virus that can affect nearly everyone at some point in life.

Quick summary

["It helps determine if you’ve been exposed to CMV and whether your immune system has produced antibodies to fight it."]

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

Key facts at a glance

LOINC
6381-8
Short code
CMV Ag Spec Ql IF
Synonyms
CMV Ag Spec Ql IF
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
if
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

What This Test Measures

The test detects the presence of Immunoglobulin G (IgG) antibodies against CMV. IgG antibodies are typically produced after an initial infection or vaccination and remain in your system for long-term protection. This test is used to identify past exposure to CMV rather than an active infection.

Why It’s Done

Doctors may order this test if you have symptoms of CMV infection (such as fever, fatigue, or organ damage), if you’re immunocompromised (e.g., due to HIV, chemotherapy, or organ transplant), or if you’re pregnant to assess potential risks to your baby.

Sample Collection and Preparation

A blood sample is drawn from a vein in your arm. The serum portion of the blood is then tested for CMV IgG antibodies using an immunoassay method.

What to Expect Before the Test

No special preparation is needed, but inform your healthcare provider about any medications you’re taking, especially blood thinners or immunosuppressants.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CMV IgG Antibody

Frequently asked questions

Will this test show if I currently have CMV?
No, this test specifically measures IgG antibodies, which indicate past exposure rather than an active infection. If you suspect an active CMV infection, your doctor may recommend additional tests.
What does a positive result mean for my health?
A positive result means your body has produced antibodies to CMV, which usually means you’ve recovered from an infection or were exposed in the past. However, if you’re immunocompromised or pregnant, further evaluation may be needed to assess risks or guide treatment.
Can I get this test at home?
No, this test requires a blood sample collected by a healthcare professional in a clinical setting. Home collection options are not available for this specific test.
  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