Pediatric Bone Marrow Transplant Procedure

July 23, 2025

This page was reviewed under our medical and editorial policy by Anna Pawlowska, M.D., clinical professor, and Nicole Karras, M.D., associate clinical professor, Department of Pediatrics, City of Hope^® Cancer Center Duarte. 

A ​​pediatric bone marrow transplant is a procedure used to treat certain ​​childhood cancers and certain non-malignant diseases. The most common conditions treated with a bone marrow or stem cell transplant in children are ​​childhood leukemia and lymphoma, and other ​​types of blood cancer. A bone marrow transplant is sometimes also called a hematopoietic stem cell transplantation (or HCST).

Bone marrow is a soft tissue found in the hollow cavities of the body’s bones. It plays an essential role in how the human body produces a wide range of cells. These include blood cells, platelets and immune system cells, as well as cells that develop into bone, cartilage and fat.

A pediatric bone marrow transplant is a procedure in which bone marrow that has been damaged by disease or invasive treatment for cancer is replaced with an infusion of healthy stem cells taken from their own body, a healthy stem cell donor or an umbilical cord. This complex procedure is performed by childhood cancer experts at a dedicated cancer center.

Who Is Part of an HSCT Treatment Team?

Children and adolescents who receive a bone marrow transplant are cared for by a team of childhood cancer doctors, oncology nurses and other specialists with expertise in performing HSCT treatments. This team may include:

• Pediatric hematologist-oncologists with expertise in treating childhood blood cancers and disorders
• A team of clinical providers who are specialty-trained in administering and managing bone marrow and stem cell transplants
• Trained pediatric oncology nurses, who care for patients during hospital or clinic stays
• Supportive care staff who specialize in providing physical and emotional support services for patients and their loved ones
• Nutrition and dietary experts, who can provide guidance on how to make diet adjustments before and after an HSCT
• Physical therapy providers with expertise in helping patients manage their recovery from a bone marrow transplant

Depending on patients’ unique needs, what type of cancer they have and how old they are, their care team may include other medical providers who help manage their health and wellbeing before, during and after an HSCT.

What Is the HSCT Process?

A bone marrow transplant is a complex medical procedure. Cancer doctors and HSCT experts work closely with patients and their loved ones as they prepare for and receive a bone marrow transplant to ensure that the procedure is administered as safely, effectively and comfortably as possible. There are several key stages to the bone marrow transplant process.

Preparation: Before a bone marrow transplant, patients may undergo a variety of tests to ensure they are eligible to receive an HSCT and healthy enough to undergo the process. These may include ​​blood tests, imaging scans and ​​bone marrow biopsy. Doctors may also place a central venous catheter (or CVC) in the body. A CVC allows doctors to draw blood or deliver medicine.

Harvesting bone marrow: Next, bone marrow is collected in the form of stem cells. When the stem cells are collected, it‘s typically done either using peripheral stem cell collection via apheresis or by bone marrow harvest (typically via the pelvic bone). It may be taken from the patient themselves (in which case it is called an ​​autologous stem cell transplant), from a healthy donor (an ​​allogeneic stem cell transplant) or from umbilical cord blood. In some cases, the collected bone marrow is frozen until it is needed for the HSCT procedure.

Bone marrow conditioning: Before patients may receive a bone marrow transplant, they must undergo bone marrow conditioning, also called bone marrow preparation or pre-transplant conditioning. This process involves the use of ​​radiation therapy or ​​chemotherapy to kill any cancer cells in the body and create more space for new, healthy bone marrow. This process usually takes 1 to 2 weeks.

Bone marrow transplantation: During the bone marrow transplant procedure itself, the healthy stem cells/bone marrow are delivered into the patient’s body via an infusion through the CVC. The process takes only one session. Patients and doctors often refer to the day they received the transplant as “day zero.”

Engraftment and recovery: After a bone marrow transplant, a child will stay in the hospital for four to six weeks (total six to eight weeks with the conditioning regimen). Most patients need three to six weeks before they’re discharge-ready. After discharge, children attend clinic visits twice weekly until day 100 (for an allogeneic transplant). If the patient lives more than one hour away from the hospital, they typically need to stay in the vicinity of the treatment center until day 100.

Rehabilitation and at-home recovery: It may take up to 6 months for bone marrow transplant patients to have normal blood counts again, and up to a year to recover fully from the procedure. During this time, they will be monitored closely by their care team for any signs of side effects, such as the body rejecting the transplant, or other health issues related to their HSCT.

Pediatric Dosing Guidelines

When patients receive a bone marrow transplant, it’s important that they receive the correct dosing. The dose of stem cells is based on the patient’s body weight. Smaller patient needs a lower number of stem cells. The dosing for a pediatric bone marrow transplant patient is different from the dosing for an adult patient, in part because a child’s bone marrow is still developing and has a slightly different composition than an adult’s bone marrow. This underscores the importance of performing HSCT for pediatric patients within specialized pediatric cancer centers.

Recovery

Children and adolescents who receive a bone marrow transplant begin their recovery in the hospital, with some patients remaining in the hospital for 6 to 8 weeks. After this, most patients recover fully at home or, if they live far from the treatment center, they stay in the vicinity of the hospital until day 100 . During this time, they may feel tired and weak and have a compromised immune system, which means it's important to reduce the chances they do things that could make them sick. A patient’s care team may recommend several steps during at-home recovery, including:

• Limiting exposure to germs or environmental irritants, like dust
• Avoiding certain foods and drinks that are raw or unpasteurized and avoid situations where food is shared, such as buffets
• Cleaning all surfaces in the home to remove dust or mold and mildew
• Replacing any filters in the home’s HVAC system with new ones
• Closing any doors and windows as much as possible

The care team will let family members know when it’s safe for the patient to return to school or other activities.

Complications

As with any significant medical procedure, a pediatric bone marrow transplant does come with some potential side effects and complications.

Nausea, vomiting and mouth pain: These are common immediately after a bone marrow transplant. They are treated with medication.

Graft-versus-host disease: This is a common complication for patients who receive stem cells from a healthy donor. It occurs when the donor's cells (the "graft") attack the recipient's body (the "host") because they see the recipient's cells as foreign. This attack can cause a range of symptoms and complications, depending on the type and severity of GVHD. It's most common within the first year of an HSCT. All patients will receive GVHD prophylaxis, which involves preventative measures to reduce GVHD risk. This complication usually resolves, but some people may require long-term treatment for the condition.

Infection: This may be potentially dangerous, since patients’ immune systems are compromised. In most cases, doctors prescribe antibiotics during recovery in order to minimize the risk of infection after a bone marrow transplant. However, if a patient has any signs of an infection, they should see their doctor straight away.

Lung health issues: These may affect patients at any time after an HSCT. However, a condition called interstitial pneumonitis is particularly common within the first few months. Doctors monitor for this condition and other lung or breathing problems during recovery, but always notify the care team right away if any breathing issues occur.

Hepatic veno-occlusive disease (VOD): This is a rarer but potentially life-threatening condition in which the blood vessels in the liver become blocked, causing problems with how the liver functions. The signs of VOD include jaundice, dark urine and pain in the abdomen. Patients or caregivers should contact their care team immediately if they notice any of these symptoms.

Other complications: Other issues are also possible later in life, including cancer returning, a new cancer diagnosis or issues with fertility. Speak to the care team for a personalized prognosis and plan for what to expect.