kids

What Is Bone Marrow?

Bone Marrow

Say: MAIR-oh

Bone marrow is a thick, spongy kind of jelly inside your bones. Bone marrow makes all kinds of blood cells: red blood cells that carry oxygen, white blood cells that fight infections, and platelets that help blood clot.

Looking for help?

Contact us

If you have questions, find the number you need to get help and support.

Find a doctor

Find a doctor, hospital, or pharmacy.

Documents & forms

Find the documents and forms you need, including your Member Handbook.