The Budd-Chiari syndrome (BCS), characterized by the obstruction and occlusion of the suprahepatic veins, is a rare but typical complication occurring in patients with polycythemia vera (PV). We describe three young women who developed BCS as first manifestation of PV, in association with an inherited thrombophilic state and in the absence of concomitant use of oral contraceptives. Our report illustrates the existence of an aggressive form of myeloproliferative disorder, which requires prompt recognition and immediate therapeutic intervention including cytostatic drugs and anticoagulant treatment. Furthermore, we suggest the need of routine screening for thrombophilic state in young women affected by PV.