There are medical guidelines for bone marrow donations that have been established by the National Marrow Donor Program (NMDP) to protect the safety of the donor and provide the best possible outcome for the patient. The height and weight guidelines for donors allow for a Body Mass Index (BMI) of up to approximately 40. Possible complications with donors that have a higher BMI include increased risk for anesthesia for bone marrow donation and comprised venous access for PBSC collection.