This is a prospective, randomized and controlled study to find out if a rotational thromboelastometry(ROTEM) guided treatment protocol reduces the need for blood transfusions in major obstetric haemorrhage compared to standard care of clinical decision making, conventional coagulation tests and massive transfusion protocol. Secondary aim is to find out if ROTEM can predict the incidence of thromboembolic events in this patient group.

A comparison of two different treatment protocols is made in patients suffering major obstetric haemorrhage: those who after a normal delivery are bleeding more than 1000 ml and are in need of surgical intervention to control the bleeding and those in cesarean section with ongoing bleeding of more than 1000 ml. Patients are randomized in to two groups: the control group(n=30) will be treated according to a protocol based on clinical decision making, standard coagulation tests and massive transfusion packages of blood products(1:1:1), if needed. This is referred as 'Standard care' in this hospital. The intervention group(n=30) will be treated according to a rotational thromboelastometry guided protocol, and massive transfusion packages, if needed. The study is powered to detect a reduction of one unit in red blood cell transfusion. Blood product, fibrinogen concentrate, prothrombin complex concentrate usage and total amount of blood loss will be compared, and the number of transfusion related side effects and thromboembolic events 30 days after the bleeding will be recorded.

Inclusion Criteria:

• Age over 18
• Severe post-partum haemorrhage ie. active bleeding of more than 1000ml within 24 hours after vaginal delivery or cesarean section
• Informed consent (after randomization)

Exclusion Criteria:

• Known hemophilia or von Willebrand's disease
• Unacceptance of allogeneic blood products(Jehovah's witnesses)