This paper reports on a 22-yr old female patient with recurrent bouts of Henoch-Schönlein purpura since puberty occurring monthly at the time of menstruation. Remissions occurred during pregnancy, and on several occasions and in a dose responsive manner when the patient was prescribed birth control pills containing progesterone and oestradiol. Flares recurred when this therapy was discontinued. We hypothesize that this patient has an inflammatory disease involving neutrophil activation by excessive IgA, which is modulated by exogenous and endogenous sex steroids. It is unlikely that these hormonal influences are a common occurrence, but rather represent, in this case, a singular example of potential endocrine modulation of inflammatory disease.