Hematocrit (cont.)

Medical Author:
Medical Editor:

What is a normal hematocrit?

The normal ranges for hematocrit are depend on the age and, after adolescence, the sex of the individual. The normal ranges are:

  • Newborns: 55% to 68%
  • One (1) week of age: 47% to 65%
  • One (1) month of age: 37% to 49%
  • Three (3) months of age: 30% to 36%
  • One (1) year of age: 29% to 41%
  • Ten (10) years of age: 36% to 40%
  • Adult males: 42% to 54%
  • Adult women: 38% to 46%

These values may vary slightly among different laboratories.

What does a low hematocrit mean?

A person who has a low hematocrit is referred to as being anemic. There are many reasons for anemia. Some of the more common reasons are loss of blood (traumatic injury, surgery, bleeding, and colon cancer), nutritional deficiency (iron, vitamin B12, folate), bone marrow problems (replacement of bone marrow by cancer, suppression by chemotherapy drugs, kidney failure), and abnormal hemaglobin (sickle cell anemia).

What does a high hematocrit mean?

Higher than normal hematocrit levels represent abnormally elevated red blood cell counts. High hematocrits can be seen in people living at high altitudes and in chronic smokers. Dehydration produces a falsely high hematocrit that disappears when proper fluid balance is restored. Some other infrequent causes of an elevated hematocrit are lung disease, certain tumors, a disorder of the bone marrow known as polycythemia rubra Vera, and abuse of the drug erythropoietin (Epogen) by athletes for "blood doping" purposes.

REFERENCE:

Braunwald, Eugene, et al. Harrisons's Principles of Internal Medicine. 17th ed. McGraw-Hill, 2008.


Medically Reviewed by a Doctor on 4/10/2014

Patient Comments

Viewers share their comments

Hematocrit - Cause Question: What was the cause of your low hematocrit reading?

STAY INFORMED

Get the Latest health and medical information delivered direct to your inbox!