Endomterisois is usually found in women of child-bearing age. A case is presented of massive right-sided pleural effusion caused by endometriosis. The final diagnosis was made by thoracoscopic pleural biopsy. Physicians should be aware of this potentially treatable cause of pleural effusion having excluded other possibilities such as malignancy and tuberculosis.
Keywords: Catamanial hemothorax; pleural endometriosis; recurrent pleural effusion.