Coagulation of blood is an important part of haemostasis but disorders in coagulation can lead to increased haemorrhage (bleeding tendency) and/or thrombosis and embolism (hypercoagulable states). Diagnostic procedures and treatment regimens for obstetric patients with pre-existing or intraoperative coagulation defects are increasingly challenging. Indications and thromboprophylaxis regimens are better understood and the impact of such treatment on patients undergoing regional anaesthesia should not be missed.