Diagram showing the normal progression of severe PPH Diagram showing the normal progression of severe PPH. Use of the PPH Butterfly should provide an early diagnosis of the underlying cause of the bleeding while preventing on-going blood loss. Diagram showing the normal progression of severe PPH. Use of the PPH Butterfly should provide an early diagnosis of the underlying cause of the bleeding while preventing on-going blood loss. PPH, postpartum haemorrhage. Caroline Cunningham et al. BMJ Innov 2017;3:45-54 Copyright © BMJ Publishing Group Ltd & British Cardiovascular Society. All rights reserved.