Contemporary usage of the term bloodless surgery refers to both invasive and noninvasive medical techniques and protocols, and the phrase itself is somewhat confusing.[6] The expression does not mean "surgery that makes no use of blood or blood transfusion". Rather, it refers to surgery performed without transfusion of allogeneic blood.[7][8] Champions of bloodless surgery do, however, transfuse products made from allogeneic blood and they also make use of pre-donated blood for autologous transfusion.[9] Interest in bloodless surgery has arisen for several reasons. Jehovah's Witnesses reject blood transfusions on religious grounds; others may be concerned about bloodborne diseases, such as hepatitis and AIDS.