[Catamenial pneumothorax due to pulmonary endometriosis]

Endometriosis is a chronic condition causing menstrual pain, irregular bleeding and infertility among women. Although usually in the pelvis, it can manifest in atypical places. We describe a 39-year old woman with a previous endometriosis diagnosis who presented three times on the second menstrual day with dyspnea and chest pain. Imaging showed right-sided pneumothorax on all three occasions. Thoraco-scopy revealed endometriosis-like lesions. Histology was suggestive of endometriosis. After treatment with chemical pleurodesis and hormonal suppression she has remained symptom-free. Diagnosis should be obtained by concomitant thoraco- and laparoscopy with biopsies to verify the disease and give a basis for appropriate treatment.