Cytomegalovirus (CMV) IgG Antibody, Serum/Plasma

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

This test measures the presence of antibodies to the cytomegalovirus (CMV), a common virus that can affect nearly everyone at some point in their lives. Antibodies indicate your immune system has recognized and fought off the virus in the past.

Quick summary

["This test helps determine if you’ve had CMV infection before."]

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

Key facts at a glance

LOINC: 34944-9
Short code: CMV IgG+IgM Pnl CSF
Synonyms: CMV IgG+IgM Pnl CSF
Category: chemistry
Sample: csf
Container: Sterile tube
Units: N/A
Fasting: false
Population: adult
Sex: all
Age range: 18–65 years
CPT: 82784
Specimen volume: 1-2 mL
Stability: Immediate analysis required, Refrigerated: 1h
Hemolysis max: 200
TAT: 4–24 hours
Order: routine

What Does This Test Measure?

The CMV IgG antibody test detects immunoglobulin G (IgG) antibodies specific to CMV. IgG antibodies develop after an initial infection and remain in your blood for a long time, often for life. This test is used to confirm past exposure to CMV rather than active infection.

Why Might Your Doctor Order This Test?

Your doctor may recommend this test if you have symptoms suggestive of CMV infection (such as fever, fatigue, or organ-specific issues), if you’re immunocompromised (e.g., due to HIV, chemotherapy, or organ transplant), or if you’re pregnant and at risk of passing CMV to your baby.

When Might You Need This Test?

You might need this test if you’ve had unexplained symptoms, if you’re undergoing treatment that weakens your immune system, or if you’re planning pregnancy and want to assess potential risks.

What Does a Positive Result Mean?

A positive result means your body has produced IgG antibodies to CMV, suggesting you’ve likely had an infection at some point. This doesn’t indicate whether you’re currently infected or if symptoms are present.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

A positive CMV IgG result is important for monitoring immunocompromised patients, guiding prenatal care, and assessing risk for transmission. It helps doctors tailor treatments or preventive measures based on your exposure history.

Short name

CMV IgG Antibody

Frequently asked questions

What does a positive CMV IgG test mean for my health?

A positive result means you’ve had CMV in the past, but it doesn’t show if you’re currently infected. It’s primarily useful for tracking immunity or assessing risk in certain medical situations.

Will this test show if I have active CMV infection?

No, this test only detects past infection. For active infection, your doctor may order a separate test (like CMV IgM or viral load) to check for current symptoms or viral activity.

Can I get CMV from my partner or family?

Yes, CMV is highly contagious and can spread through bodily fluids. If you’re immunocompromised, it’s especially important to avoid close contact with people who may have symptoms or infections.

Sources

1
MedlinePlus — Laboratory TestsSource
2
Lab Tests OnlineSource
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