Reasons, Preparation, Procedure & Results of MCH Blood Test

Submitted on March 27, 2012

Blood tests are said to be very important as they tell a lot about a person's health. A Complete Blood Count test may generally be conducted to determine the presence of any diseases or disorders in the body. This entails examining the different components of your blood that include white blood cell count, red blood cell count, a platelet count, along with mean corpuscular volume, the hemoglobin, hematocrit mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and also red cell distribution width. The red blood cell count plays a crucial role in determining the various types of anemia and the inability of the blood to carry enough oxygen.

Reasons For Conducting The Test

MCH blood test, known as Mean Corpuscular Hemoglobin is a test conducted to know the average weight of hemoglobin that is present inside a red blood cell. The main responsibility of hemoglobin is to carry oxygen to the blood. It is composed of a group of amino acids that contain iron atoms which gives the red color to hemoglobin. MCH, MCV and MCHC are three main red blood cell indices that help in measuring the average size and hemoglobin composition of the red blood cells. A low MCH indicates an iron deficiency whereas a high MCH results in too much hemoglobin present which causes insufficient supply of oxygen to the blood.


There are no specific preparations that are required for the test unless the doctor specifies otherwise. You may be asked not to consume any fatty meals a few hours prior to taking the test.


MCH is a blood test and is taken by removing blood from your vein which is then given for further testing. A sample of your blood can also be collected by pricking a sharp instrument, which is similar to a needle, on your finger tip and making it bleed. Normal MCH blood test results do not indicate any problems and therefore there is nothing to worry about. These normal results will have the mean corpuscular hemoglobin within the range of 27 to 33 picograms per cell. MCH blood test high indicates that there is a poor supply of oxygen to the blood where as MCH blood test low mean that hemoglobin is too little in the cells indicating a lack of iron. It is important that iron is maintained at a certain level as too much or too little iron can be dangerous to your body.

Our blood consists of various components each with its own function. Red blood cells or red corpuscles are so called because of the presence of iron, which gives the blood its red color. A protein called hemoglobin present in red corpuscles helps carry oxygen to our lungs. White blood cells or white corpuscles act as our body's natural body guards or soldiers against disease, viral infections, and intolerance to certain medicines. Their count increases when there is an injury or infection. There are five types of white corpuscles, and there is cause for concern if the numbers go beyond or below the standard count.

When there is an injury, platelets are formed at the site in order help in blood clotting to 'close the wound'. Increase or decrease in their numbers lead to problems in proper blood clotting and excessive bleeding respectively. In an MCH blood test, a complete blood test (CBC) is recommended to determine various blood and organ disorders in our body. The size, number and density of the red corpuscles in the blood are proportional to the hemoglobin content and subsequently the amount of oxygen they can transport. Test results also provide number of red corpuscles and quantity of hemoglobin in the blood, white corpuscles, and ratio of red corpuscles and blood.

MCH stands for mean corpuscular hemoglobin. It refers to the quantity of hemoglobin in red corpuscles. To have your MCH blood test results explained you would need to visit the doctor. MCH is determined by the percentage of red cells and the amount of hemoglobin present in blood. An MCH blood test is carried out to determine hemoglobin in the red corpuscles to diagnose anemia.

Reasons For Elevated & Dropped MCV Levels In People

MCH is calculated and expressed as picograms or pg per cell. The MCH blood test normal range is 27.5 to 33.5 pg. In an MCH blood test, low levels indicate iron deficiency or anaemia. An elevated MCH blood test result (high levels) indicates macrocytic anemia due to paucity of folic acid or vitamin B12 or thyroid problems. Alcoholism can also raise MCH levels.

MCV stands for mean corpuscular volume. It refers to the size of red cells in our blood. Presence red cells smaller or larger than normal sized ones, means the person has anaemia. The normal range is 80 to 97.

Elevated levels of MCV are seen in people with

  • Megaloblastic anemia caused by iron and folic acid deficiencies
  • A family history of anemia
  • Inability to recoup after severe blood loss
  • Hyperthyroidism
  • Liver disorders
  • Drugs to counter AIDS
  • Reaction to anti-convulsant drugs

There is a drop in MCV levels in people with

  • Vitamin C and copper deficiencies
  • Exposure to toxins like lead
  • Family history like sideroblastic and thalassemia

MCV and MCH blood test results should always be studied together for proper prognosis. Increase or decrease in both MCV and MCH levels are used to determine vitamin B6 or mineral (copper or iron) deficiencies and/or excess B12 and folic acid. Test results help diagnose different types of anaemia.

What does MCHC stand for?

MCHC stands for mean corpuscular haemoglobin concentration. It denotes the amount of hemoglobin in a specific volume of 'packed' red corpuscles or cells. This ratio is mentioned along with other details of a blood count in a standard blood report. MCHC denotes how much hemoglobin is present in 100 ml unit of red corpuscles. Normal ranges are from 32% to 35%. An MCHC blood test (also known as an MCH test) is conducted to test a person for anemia. If there is a low count, it indicates anemia. However, further tests are needed to be carried out before coming to any conclusion about the cause and type of anemia.