Physicians in the United States have been using stem cell-rich cord blood infusion treatments for about forty years. Members of the National Institute of Health (NIH) stated in 2003 that they see no cases of cancer or other health threats arising from stem cell therapy. Researchers at Steenblock Research Institute have yet to encounter a single instance of rejection in patients who have received pure umbilical cord stem cells. This suggests the umbilical cord stem cell therapy is safe.
The donors go through a very thorough vetting process. The initial intake form screens donors’ medical and genetic history. Only the best donors are selected to move forward. During the pregnancy, blood samples are taken from the mother to ensure there are no communicable diseases. After labor in the delivery room, a blood sample of the donated umbilical cord tissue is taken to test for illegal drug consumption, viruses, infectious disease, and genetic defects.  After the umbilical cord tissue is tested and approved at the hospital, it goes through one more testing step before being sent to the lab. During the final testing phase, the tissue is analyzed to rule out bacteria, fungi, and viruses. Finally, the umbilical cord tissue is received at the lab for cell selection and expansion.