MCHMean corpuscular haemoglobin · Mean cell haemoglobin
The average amount of haemoglobin inside each red blood cell.
Mean corpuscular haemoglobin is the average mass of haemoglobin per red blood cell, calculated by dividing the total haemoglobin by the number of cells.
It matters as part of classifying anaemia. Cells low in haemoglobin appear pale under a microscope, and that pattern points towards iron deficiency or an inherited haemoglobin disorder, whereas anaemia with normal or high MCH points elsewhere, such as B12 or folate.
In practice MCH moves closely with MCV, since smaller cells hold less haemoglobin, and the two are read together with ferritin and the rest of the count rather than alone.