Does piercing needle donate bone marrow hurt? Is it the same as drawing blood?

There are two methods to extract hematopoietic stem cells from the bone marrow: one is that the doctor piercingly collects hematopoietic stem cells from the bone marrow at the iliac bone of the donor. There will be some pain within a day or two after the operation, and the patient will recover completely within a week. Second, hematopoietic stem cells from bone marrow and other parts are effectively mobilized in a scientific way and released into the peripheral blood in large quantities. Hematopoietic stem cells are collected from the arm vein of the donor and separated by a machine. The remaining blood is transfused into the donor.

It doesn't hurt, just like when you get an infusion