A red blood cell (RBC) count may be ordered by a physician as part of a complete blood cell (CBC) count. A RBC count is the number of red blood cells per volume of blood, and is reported in either millions in a microliter or millions in a liter of blood.
Levels of RBCs out of the normal range (higher or lower) can be an indication of certain conditions. Polycythemia is the presence of an elevated RBC count; anemia is a decreased RBC count.
A blood sample will be taken, normally from the arm. If several tests are ordered, more than one vial of blood will be taken. If your RBC count has been low in the past, taking blood might seem counterproductive, but the CBC count can be a very useful tool to your physician in diagnosing and treating many health conditions.
The ranges for a normal RBC count (expressed in million red cells per microliter {uL} of blood) are:
- Women: 4.2 to 5.4 million/uL
- Men: 4.7 to 6.1 million/uL
- Children: 4.6 to 4.8 million/uL

