Intra-abdominal bleeding from the corpus luteum developed in three women receiving anticoagulant treatment. In one of these patients, no other hemorrhagic manifestations were present. Bleeding from corpus luteum should be considered in differential diagnosis of low abdominal pain in women of reproductive age receiving anticoagulant therapy. The ovary has not been widely recognized as a site of hemorrhage complicating anticoagulant therapy, although abdominal bleeding in this location may be more common than previously thought. Thorough clinical studies are needed to establish the precipitating factors and true incidence of this complication.