MCH, or mean corpuscular hemoglobin, is an important measurement of the average amount of oxygen-carrying protein inside your red blood cells. Specifically, MCH indicates the average concentration of hemoglobin per individual red cell in your body.
Alongside other red blood cell indices, MCH levels help doctors diagnose different types of anemia or blood disorders. Low MCH typically signals conditions interfering with normal hemoglobin production like iron deficiency, thalassemia, or chronic illness. Elevated MCH can indicate megaloblastic anemia from vitamin B12 or folate deficiency instead.
During a standard complete blood count test, MCH serves as one key indicator of red blood cell health. Tracking trends in MCH over time can reveal developing issues like anemia or abnormal hemoglobin present before symptoms appear. Evaluating MCH test results within your wider medical context aids clinical decisions about further testing or interventions for maintaining optimal health.
What is MCH?
MCH stands for “mean corpuscular hemoglobin”. It is a measurement of the average amount of hemoglobin inside a single red blood cell.
Hemoglobin is the protein in red blood cells that carries oxygen. It gives blood its red color and serves the critical function of transporting oxygen from the lungs to tissues and cells throughout the body.
Why Test MCH?
MCH testing provides insight into the average hemoglobin content in individual red blood cells. Along with other red blood cell indices like MCV and MCHC, MCH helps evaluate anemia and other blood disorders.
Abnormal MCH levels indicate potential problems like:
- Iron deficiency anemia – low MCH
- Megaloblastic anemia – high MCH
- Thalassemias – low MCH
In particular, MCH helps differentiate between iron deficiency anemia vs thalassemia which can have similar symptoms.
The MCH blood test is often part of a complete blood count (CBC) performed during routine health screening or to investigate symptoms like fatigue, pale skin, dizziness etc.
Understanding MCH Test Results
Normal lab reference ranges for MCH are:
- Adult Males: 27-33 picograms/cell
- Adult Females: 26-33 picograms/cell
Low MCH levels indicate:
- Iron deficiency reducing hemoglobin production
- Thalassemias causing abnormal hemoglobin
- Anemia from chronic disease, bleeding or deficiencies
High MCH can signal:
- Vitamin B12/folate deficiency
- Liver disease and other conditions
Evaluating MCH alongside MCV and MCHC helps determine specific causes of abnormal results.
Additional Key Points about MCH:
MCH levels fluctuate slightly with pregnancy, smoking, age etc. requiring interpretation alongside wider symptoms
- High altitude environments can temporarily impact MCH ranges
- Bone marrow damage, hematologic cancers and chemotherapy can affect MCH
Frequently Asked Questions about MCH:
How is the blood sample collected for MCH testing?
An MCH test requires having blood drawn from a vein, usually in the arm. Blood collection is quick and minimal discomfort felt.
Do I need to fast for an MCH blood test?
No fasting is necessary prior to having your blood drawn for an MCH test. You can eat and take any medications normally.
Why is my MCH low but MCV and other counts normal?
This pattern can indicate alpha or beta thalassemia traits, confirming requires additional hemoglobin analysis. Iron deficiency can also cause isolated low MCH.
Why is my MCH level high?
Megaloblastic anemias from vitamin deficiencies, some leukemias, alcoholism, reticulocytosis or anti-malarial drug use can drive MCH levels higher.
How often should MCH be tested?
For healthy patients, MCH testing every 1-2 years suffices unless symptoms appear. Higher risk groups may need annual monitoring of red blood cell indices.
Let your doctor know if you have any symptoms like severe fatigue, weakness or skin pallor so appropriate bloodwork including an MCH can be ordered to investigate underlying causes. Catching issues early is beneficial.
In summary, MCH testing provides vital insights into red blood cell health and can screen for dangerously low hemoglobin levels. Discuss results with your doctor to determine next steps based on your health profile. Tracking MCH over time illuminates developing issues.
