The hemoglobin test is normally ordered as a part of the complete blood count (CBC) , which is ordered for many different reasons, including for a general health screen. The test is also repeated in patients who have ongoing bleeding problems or chronicanemias or polycythemia.
Hemoglobin decreases slightly during normal pregnancy.
Hemoglobin levels peak around 8 a.m. and are lowest around 8 p.m. each day.
Heavy smokers have higher hemoglobin levels than nonsmokers.
Living in high altitudes increases hemoglobin values due to an increase in the number of red blood cells. Your body produces more red blood cells in response to the decreased oxygen available at these heights.
Hemoglobin levels are slightly lower in older men and women and in children.
This article was last reviewed on March 4, 2008.
This page was last modified on April 8, 2009.
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