<p>Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The stem cells can develop into red blood cells, which carry oxygen throughout the body, white blood cells, which fight infections, and platelets, which help the blood to clot.</p> <p>A bone marrow transplant is a procedure that replaces a person's faulty bone marrow stem cells. Doctors use these transplants to treat people with certain diseases, such as:</p><ul> <li><a href="https://medlineplus.gov/leukemia.html">Leukemia</a></li> <li>Severe blood diseases such as <a href="https://medlineplus.gov/thalassemia.html">thalassemias</a>, <a href="https://medlineplus.gov/aplasticanemia.html">aplastic anemia</a>, and <a href="https://medlineplus.gov/sicklecelldisease.html">sickle cell anemia</a></li> <li><a href="https://medlineplus.gov/multiplemyeloma.html">Multiple myeloma</a></li> <li>Certain immune deficiency diseases</li> </ul> <p>Before you have a transplant, you need to get high doses of chemotherapy and possibly radiation. This destroys the faulty stem cells in your bone marrow. It also suppresses your body's immune system so that it won't attack the new stem cells after the transplant.</p> <p>In some cases, you can donate your own bone marrow stem cells in advance. The cells are saved and then used later on. Or you can get cells from a donor. The donor might be a family member or unrelated person.</p> <p>Bone marrow transplantation has serious risks. Some complications can be life-threatening. But for some people, it is the best hope for a cure or a longer life.</p> <p class="">NIH: National Heart, Lung, and Blood Institute</p>