What do blood counts mean

If your health care provider has also ordered other blood tests, you may need to fast not eat or drink for several hours before the test. Your health care provider will let you know if there are any special instructions to follow. There is very little risk to having a blood test.

You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly. A CBC counts the cells and measures the levels of different substances in your blood. There are many reasons your levels may fall outside the normal range.

For instance:. If any of your levels are abnormal, it does not necessarily indicate a medical problem needing treatment. Diet, activity level, medications, a women's menstrual cycle, and other considerations can affect the results. Talk to your health care provider to learn what your results mean.

Learn more about laboratory tests, reference ranges, and understanding results. A complete blood count is only one tool your health care provider uses to learn about your health. Your medical history, symptoms, and other factors will be considered before a diagnosis. Additional testing and follow-up care may also be recommended.

The information on this site should not be used as a substitute for professional medical care or advice. Your blood count can help your doctor pinpoint diseases such as anemia or cancer, clotting issues, and infection.

A blood count test also can help determine if you have an immune system disorder. Normal blood count ranges depending on your gender and age. In general, the normal range for a red blood cell count is 4. Children and pregnant women may have different normal counts, so talk to your doctor about the results. A blood count test provides a variety of information about your health. For example, a low red blood cell count could mean you have anemia, while a low white blood cell count could signify neutropenia , a condition that puts you at a higher risk for infection.

An abnormal platelet count may indicate you have a blood clotting disorder, like thrombocytopenia. Chemotherapy and radiation treatment also can cause a low platelet count. Driving Discovery. Highlighted Scientific Opportunities. Research Grants. Research Funding Opportunities. Cancer Grand Challenges. Research Program Contacts. Funding Strategy. Grants Policies and Process. Introduction to Grants Process. NCI Grant Policies. Legal Requirements. Step 3: Peer Review and Funding Outcomes.

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