The prospect of dealing with a rapidly and inexorably bleeding patient fills most medical practitioners with alarm. When that patient is a Jehovah's Witness, the knowledge that a blood transfusion is likely to be refused turns that alarm into a state of acute anxiety and conflict. This state is further heightened when the patient is young and otherwise healthy--a situation found particularly in obstetric practice with the occurrence of ante- and post-partum haemorrhage, and ectopic pregnancy. In the last 25 years in England, Wales, Scotland and Northern Ireland, there has been one maternal death in which the refusal to accept a blood transfusion has been considered to be an avoidable factor. In this article I have attempted to identify the magnitude of the problem in obstetric practice and have sought to clarify the moral and legal aspects.