Budd-Chiari syndrome still represents a challenge for the hepatologist with regard to its causes and its most effective therapy. Polycythemia vera is considered to be the most frequent condition causing the Budd-Chiari syndrome (10-40% of cases). We present a 34-year-old patient in post-partum who was admitted for right upper abdominal quadrant pain and asthenia. Laboratory data, abdominal echography and angioMRI all raised the suspicion of BCS, but it was in the haematological department that polycytemia vera was diagnosed as the cause of the hepatic condition.