Catamenial pneumothorax. Bilateral occurrence while on suppressive therapy.

A case of recurrent bilateral catamenial pneumothorax is presented with pathologic, cytologic, and radiologic documentation. Unlike previously reported cases where the pneumothorax is unilateral and the symptoms relieved while ovulation is suppressed with cyclic oral contraceptives, in the present case the pneumothorax occurred despite oral contraceptive therapy concurrent with anovulatory withdrawal or breakthrough bleeding.