Autoimmune progesterone dermatitis.

A 35-year-old woman had recurrent urticarial erythemas on her trunk and extremities for 3 years. The eruptions appeared regularly 3 to 5 days prior to menstruation and persisted for several days. The patient showed a positive skin test response to progesterone and had circulating antiprogesterone IgG antibodies. A speculative concept of the possible autoimmune damage to the ovary, the major organ producing progesterone, is discussed.