The erythropoietin test measures the amount of a hormone called
erythropoietin (EPO) in blood. The hormone tells stem cells in
the bone marrow to make more red blood cells. EPO is made by
cells in the kidney. These cells release more EPO when blood
oxygen levels are low. See also: Reticulocyte count A blood
sample is needed. For information on how this is done, see:
Venipuncture No special preparation is necessary. When the
needle is inserted to draw blood, some people feel moderate
pain, while others feel only a prick or stinging sensation.
Afterward, there may be some throbbing. This test may be used to
help determine the cause of anemia, polycythemia (high red blood
cell count) or other bone marrow disorders. A change in red
blood cells will affect the release of EPO. For example, persons
with anemia have too few red blood cells, so more EPO is
produced. The normal range is 0-19 milliunits per milliliter
(mU/mL). The examples above are common measurements for results
of these tests. Normal value ranges may