Overview

Bone marrow aspiration and bone marrow biopsy are procedures to collect and examine bone marrow — the spongy tissue inside some of your larger bones.

Bone marrow aspiration and bone marrow biopsy can show whether your bone marrow is healthy and making normal amounts of blood cells. Doctors use these procedures to diagnose and monitor blood and marrow diseases, including some cancers, as well as fevers of unknown origin.

Bone marrow has a fluid portion and a more solid portion. In bone marrow aspiration, a needle is used to withdraw a sample of the fluid portion. In bone marrow biopsy, a needle is used to withdraw a sample of the solid portion.

Bone marrow aspiration can be performed alone, but it's usually combined with bone marrow biopsy. Together, these procedures may be called a bone marrow exam.