Mean Corpuscular Volume (MCV)
Mean corpuscular volume measures the average size of red blood cells. MCV increases gradually with age in both sexes, and the sex difference is small compared to other CBC markers.
Unit: fL · 12 slices · age and sex · 1 source
Filed under panels: Complete Blood Count · topics: Hematology
Mean corpuscular volume (MCV) is the average volume of a single red blood cell, expressed in femtoliters (fL). It is calculated from hematocrit and red blood cell count. MCV is the primary index used to classify red cell morphology as microcytic, normocytic, or macrocytic. It increases with age, partly reflecting subclinical B12 and folate changes and shifts in red cell production dynamics.
Population Distribution
Browse by Demographic
| Age (years) | male (fL) | female (fL) |
|---|---|---|
| 20-29 | 81–94.1 (88) | 77.7–95.3 (88.1) |
| 30-39 | 81.4–95.1 (88.1) | 76.6–95.5 (89.3) |
| 40-49 | 81.6–96 (89.6) | 74.5–96.5 (88.8) |
| 50-59 | 81.8–96.8 (89.5) | 78.2–96.5 (89.3) |
| 60-69 | 81.7–98.1 (90.5) | 80.7–97.3 (89.7) |
| 70+ | 83.2–99.2 (91.6) | 83.4–98.9 (91.1) |
Frequently Asked Questions
Why does MCV increase with age?
Several factors contribute: subclinical B12 and folate insufficiency become more common, erythropoiesis slows (producing fewer but larger cells), and chronic conditions that alter red cell production increase in prevalence.
What does MCV tell you that hemoglobin does not?
MCV describes red cell size, not oxygen-carrying capacity. Two people can have the same hemoglobin but different MCV values, pointing to different underlying physiology (for example, iron deficiency produces small cells while B12 deficiency produces large cells).
Why are these population percentiles and not clinical reference ranges?
Clinical reference ranges for MCV are derived from selected, presumed-healthy individuals and are used to flag microcytic or macrocytic values. Population percentiles describe where a value falls across the full US population, including people with subclinical nutritional deficiencies and chronic conditions. The two answer different questions.