What it measures
MCH (mean cell haemoglobin) is the average amount of haemoglobin in each red blood cell. The lab works it out from the haemoglobin result and the red cell count, so it comes as part of a full blood count.
Why people test it
- Part of a full blood count, read with MCV to describe the red cells when haemoglobin is low.
- A low figure is seen when red cells are small and pale, as with low iron.
- A high figure is seen when red cells are large, as with low B12 or folate.
Typical range
Ranges vary between labs, with the method used, age and sex, and your report shows the lab's own range. One NHS trust lab gives 27 to 32 pg for adults. Source: Gloucestershire Hospitals NHS Foundation Trust: haematology reference ranges.
Finger-prick or vein?
A vein draw is usually advised. MCH is worked out from the other blood count results, and finger-prick samples can clot or have their red cells burst (haemolyse), which upsets them.