Certain medical procedures involving blood are specifically prohibited by Jehovah's Witnesses' blood doctrine. This includes the use of red blood cells, white blood cells, platelets and blood plasma. Other fractions derived from blood are not prohibited. Watch Tower publications state that some products derived from one of the four primary components may be so similar to the function of the whole component and carry on such a life-sustaining role in the body that "most Christians would find them objectionable". For procedures where there is no specific doctrinal prohibition, individuals are to obtain details from medical personnel and then make a personal decision.
