Mean Corpuscular Volume (MCV)

What is Mean Corpuscular Volume?

Mean Corpuscular Volume (MCV) measures the average size of red blood cells in femtoliters (fL). This fundamental parameter helps classify anemia into microcytic (small cells), normocytic (normal-sized cells), or macrocytic (large cells), providing crucial diagnostic information about underlying causes of blood disorders.

Why is it Tested?

Doctors order MCV as part of every complete blood count to classify anemia types, guide further testing, and monitor treatment response. It’s the first step in anemia workup, helping distinguish between iron deficiency, vitamin deficiencies, and other causes of low red blood cell production.

Normal Ranges

Reference ranges vary by lab, but general adult guidelines:

Adults: 80–100 fL

Normal MCV values indicate properly sized red blood cells that can efficiently transport oxygen throughout the body.

Reference ranges vary by authority. Track yours across multiple standards with automatic unit conversions in LabsVault.

What do Abnormal Results Mean?

Abnormal results are not a diagnosis. Always discuss your results with a qualified healthcare provider before making any medical decisions.

Low MCV (Microcytic)

Low MCV indicates smaller-than-normal red blood cells and may suggest:

Iron deficiency anemia
Thalassemia
Chronic disease anemia
Sideroblastic anemia
Lead poisoning

High MCV (Macrocytic)

Elevated MCV indicates larger-than-normal red blood cells and may suggest:

Vitamin B12 deficiency
Folate deficiency
Hypothyroidism
Liver disease
Alcoholism
Certain medications (methotrexate, antiretrovirals)

How to Track Over Time

Tracking MCV trends helps monitor nutritional deficiency treatment and detect developing blood disorders. Rising MCV during B12 or folate supplementation indicates successful treatment, while declining values may signal developing iron deficiency or chronic disease requiring intervention.

Mean Corpuscular Volume