We report three cases of severe haemorrhagic rupture of luteal ovarian cyst requiring surgical haemostasis in young women treated with long-term oral anticoagulation for antiphospholipid syndrome (APS) who used no contraception. At the time of bleeding, the international normalized ratios were 3.78, 4.24, and 7.11. Anticoagulation was resumed post-operatively, in association with antigonadotropic progestins to induce ovulatory suppression. A systematic use of these progestins should probably be discussed in young women receiving long-term warfarin for APS. Ovarian haemorrhage must be considered when such patients develop acute abdominal pain.