Reticulocyte Count Test
A reticulocyte count measures the number of young red blood cells in your blood. It helps check if your bone marrow is making the right amount of red blood cells.
What this test measures
A reticulocyte count measures the number of reticulocytes (immature red blood cells) in your blood. Reticulocytes are made in the bone marrow and mature into red blood cells within one to two days.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
A higher-than-normal reticulocyte count may mean hemolytic anemia, new or ongoing bleeding, or hemolytic disease of the newborn.
Lower-than-normal results
A lower-than-normal reticulocyte count may mean iron deficiency anemia, pernicious anemia, aplastic anemia, bone marrow failure, kidney disease, or cirrhosis.
Frequently asked questions
What is a reticulocyte count?
It measures the number of reticulocytes (immature red blood cells) in your blood.
Why is this test done?
It is used to diagnose types of anemia, see if anemia treatment is working, check bone marrow function, or check bone marrow after chemotherapy or transplant.
What does a high reticulocyte count mean?
It may mean hemolytic anemia, new or ongoing bleeding, or hemolytic disease of the newborn.
What does a low reticulocyte count mean?
It may mean iron deficiency anemia, pernicious anemia, aplastic anemia, bone marrow failure, kidney disease, or cirrhosis.
Can other factors affect my reticulocyte count?
Yes, pregnancy, high altitude, and certain medicines can affect the count.
Related lab tests
Sources
- MedlinePlus: Reticulocyte Count — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.