A 25-year-old lady attends the ED complaining of a three-week history of vaginal bleeding. This is on a background of heavy bleeding since menarche. She has no other medical problems and takes no regular medications. Her sister had a postpartum haemorrhage and her mother required transfer to hospital due to bleeding after a routine dental extraction. She is alert with GCS 15, heart rate 83, BP 113/74, respiratory rate 12.