Six hours after an uncomplicated extended resection of ovarian cancer, postoperative arterial bleeding led to life-threatening blood loss in a 44-yr-old Jehovah's Witness who refused blood transfusion. Haemoglobin (Hb) decreased from 2.5 g dl(-1) directly after the emergency laparotomy, followed by a 10 h immeasurable period (below detectable minimum value of the analyser), to a measurable minimum of 1.5 g dl(-1) after 20 h. Haematopoiesis was induced by high-dose i.v. erythropoietin therapy (600 IU kg(-1)) and continued on days 3, 6, 8, 10 and 13. Iron, folic acid and vitamins were given as supplements. The patient needed ventilatory assistance for 18 days and some inotropic support. Complications included increases in pancreatic enzymes and liver enzymes, jaundice and skin necrosis at the fingertips and toes. Myopathy led to transient tetraparesis. Haemoglobin rose from 1.5 to 3.4 g dl(-1) (day 10) and the patient was discharged from the intensive care unit with haemoglobin 6.5 g dl(-1) on day 24. She made a full recovery and is still free of cancer in remission.