CMV Antibody Blood Test (Cytomegalovirus IgG & IgM)
Know your CMV status: past exposure or active infection.
Cytomegalovirus (CMV) is a common herpesvirus that most people encounter at some point in their lives. In healthy individuals it usually causes mild or no symptoms, but it can pose serious risks for pregnant women, unborn babies, newborns, and people with weakened immune systems. This blood test detects antibodies produced by the immune system in response to CMV, helping to distinguish between past exposure and a current or recent infection.
The test measures two types of antibodies:
CMV IgG
- Indicates past exposure or established infection. A positive IgG result generally means you have been infected with CMV at some point and have developed antibodies.
- A negative IgG result suggests no prior exposure, which is particularly important for pregnant women or those planning pregnancy, as it identifies those who are not immune.
CMV IgM
- Suggests a recent or active infection. IgM antibodies typically appear early after infection and may indicate an acute or recent CMV infection.
- However, IgM can sometimes persist for months and may cross-react with other viruses, so results are interpreted alongside IgG and clinical context.
This test is suitable for anyone concerned about CMV exposure, including pregnant women, immunocompromised individuals, and those with symptoms suggestive of CMV infection such as prolonged fever, fatigue, or swollen glands. It is also used in pre-transplant or pre-immunosuppression screening.
Why it matters
Knowing your CMV antibody status provides clarity: it can confirm immunity, identify a primary infection during pregnancy, or flag an active infection requiring medical attention. Early detection supports timely monitoring and management, helping to protect vulnerable individuals and guide clinical decisions.
CMV Antibodies
- CMV IgG
- CMV IgM
No special preparation required.
For blood tests, we recommend drinking plenty of water beforehand to ensure smooth sample collection. If you are taking any regular medication, continue to do so unless advised otherwise by your doctor.
Important Clinical Information:
This test is a screening tool to monitor and support your overall health. It does not replace your GP or Consultant.
Always discuss your test results, especially any abnormal results, with your GP, who can interpret them in the context of your medical history and overall health.