An uncommon etiology of isolated pleural effusion. The ovarian hyperstimulation syndrome.

We report three cases of pleural effusion in the context of ovarian stimulation for in vitro fertilization. The ovarian hyperstimulation syndrome usually causes pleural effusion and ascites. When the latter is lacking, an isolated pleural effusion in a pregnant patient can be mistaken for pulmonary embolism. Early recognition of the condition should allow for an appropriate diagnostic and therapeutic management. Except for some rare but life-threatening complications, such as major hypovolemia or respiratory distress syndrome, the spontaneous outcome is usually favorable. The pathogenesis of this condition may involve an increase of capillary permeability due to the release of vasoactive mediators.