At a Glance Why Get Tested? To help evaluate the bone marrow's
ability to produce red blood cells (RBCs) and to help
distinguish between anaemia related to blood loss or destruction
and anaemia related to decreased RBC production; to help monitor
bone marrow response and return of normal marrow function
following chemotherapy treatment, bone marrow transplant, or
post-treatment follow-up for iron deficiency anaemia When to Get
Tested? A blood sample obtained by inserting a needle into a
vein in the arm or sometimes from pricking a finger (or the heel
of an infant) The Test Sample What is being tested? This test
measures the number and percentage of reticulocytes in the blood
and serves as an indicator of the adequacy of bone marrow red
blood cell (RBC) production. Reticulocytes are immature red
blood cells. They are produced in the bone marrow when stem
cells differentiate to the next stage of RBC development,
eventually forming reticulocytes and finally mature RBCs. Most
RBCs are fully mature before they are