An MCV (mean corpuscular volume) blood test is a laboratory test that measures the average size of your red blood cells. Red blood cells are responsible for carrying oxygen from your lungs to every cell in your body.
The results of an MCV blood test are often part of a complete blood count (CBC). An MCV test, combined with other CBC results, can help your healthcare provider determine if you have anemia, liver disease, or other conditions.
- High MCV: A higher MCV value indicates that the red blood cells are larger than the average size, a condition called macrocytosis. This may be caused by:
- Vitamin B12 deficiency
- Folate deficiency
- Liver disease
- Alcoholism
- Certain medications
- Low MCV: A lower MCV value indicates that the red blood cells are smaller than the average size, a condition called microcytosis. This may be caused by:
- Iron deficiency anemia
- Thalassemia
- Lead poisoning
If your MCV test results are abnormal, your healthcare provider may order additional tests to determine the underlying cause.
