Mean Corpuscular Hemoglobin

MCH stands for mean corpuscular hemoglobin — the average amount of hemoglobin packed into a single red blood cell. It's a calculated value on the complete blood count (CBC), derived from your hemoglobin and red cell count, and it tracks closely with MCV (cell size). Bigger cells generally carry more hemoglobin, so MCH and MCV usually move together.

The normal MCH range is roughly 27–33 pg (picograms) per red cell. Below 27 pg the cells are described as hypochromic, meaning pale and hemoglobin-poor; above 33 pg they carry more hemoglobin than usual, which often accompanies large (macrocytic) cells. Exact cutoffs vary slightly by lab.

MCH is reported in picograms (pg), a unit of mass — one picogram is a trillionth of a gram. So an MCH of 30 means each red blood cell holds an average of 30 picograms of hemoglobin. Don't confuse it with MCHC, which is a concentration in g/dL rather than an amount per cell.

All three describe your red cells but from different angles. MCV is the average size (volume) of a cell, MCH is the average amount of hemoglobin in a cell, and MCHC is the concentration of hemoglobin within a cell (amount divided by size). MCH and MCV tend to rise and fall together, while MCHC stays more stable because it accounts for cell size.

A low MCH (hypochromia) most often points to iron-deficiency anemia or thalassemia, and it typically appears alongside a low MCV. TRT itself doesn't directly change MCH, but men doing frequent therapeutic phlebotomy or blood donation to manage a high hematocrit can gradually drain their iron stores, and that iron depletion can nudge MCH and MCV downward over time. A persistently low MCH is worth pairing with ferritin and iron studies.