A hematocrit test is a simple blood measurement that determines the proportion of red blood cells in your blood. Red blood cells are responsible for carrying oxygen from your lungs to the rest of your body. The test result is given as a percentage; for example, a result of 36.2 means that 36.2% of your blood volume is composed of red blood cells.
This measurement is often part of a complete blood count (CBC). The remaining volume consists of white blood cells, platelets, and plasma, which is the liquid component of blood.
Normal Hematocrit Ranges
The interpretation of a hematocrit level depends heavily on several factors, including age and sex. For adult women who are not pregnant, the typical normal range is between 36% and 44%. Therefore, a hematocrit level of 36.2% would fall within the low end of this normal range.
For adult men, the normal hematocrit range is higher, generally between 41% and 50%. In this context, a 36.2% level would be considered low. It is important to recognize that these ranges can vary slightly between different laboratories, so results should always be compared to the specific reference range provided by the lab that performed the test.
Children and newborns have different normal ranges as well. For children, the typical range is approximately 30% to 44%, while newborns have much higher levels, often between 45% and 61%.
Potential Causes of Low Hematocrit
A hematocrit level that is considered low, such as 36.2% for an adult male, can be an indicator of an underlying health issue. A low hematocrit level often signifies anemia, a condition characterized by a deficiency of healthy red blood cells. Common symptoms associated with low hematocrit include fatigue, weakness, shortness of breath, dizziness, and pale skin.
Nutritional deficiencies are a frequent cause, particularly a lack of iron, vitamin B12, or folate, all of which are needed for red blood cell production. Blood loss, whether from an injury, a gastrointestinal ulcer, or heavy menstrual cycles, can also lead to a decrease in red blood cell volume.
Certain chronic conditions can also impact the body’s ability to produce or maintain an adequate number of red blood cells. Chronic kidney disease can interfere with the production of a hormone that stimulates red blood cell creation. Some cancers, including leukemia, directly affect the bone marrow where red blood cells are made.
Interpreting Your Results With a Doctor
A single lab result, such as a hematocrit of 36.2%, does not provide a complete picture of your health. Various temporary factors can influence hematocrit levels. For instance, being dehydrated can falsely elevate the number, while being overhydrated can lower it.
Recent events like a blood donation or pregnancy can also affect the results. Pregnant individuals often have lower hematocrit levels because their total blood fluid volume increases, which dilutes the concentration of red blood cells. This is a normal physiological change during pregnancy.
Ultimately, the significance of a 36.2% hematocrit level can only be determined by a doctor. They will interpret this result in the context of your overall health, including your symptoms, medical history, and other laboratory tests.