A 23-year-old woman presented with millet-sized red papules that were scattered over her chest and abdomen. She stated that since the age of 20, she had recurrently suffered from pruritic eruptions that coincided with ovulation and the time prior to menstruation, and that they persisted for a few days before vanishing spontaneously leaving some pigmentation. A skin biopsy specimen revealed spongiotic bullae in the epidermis and marked infiltration of lymphocytes accompanied by some histiocytes and eosinophils in the upper dermis. An intradermal test for conjugated estrogen showed an urticarial reaction that faded in about four hours. Although the test did not strictly meet the criterion (erythema to remain for more than 24 hours for papulovesicular eruptions), it was concluded that the timing of the episodes along with the result of the test suggested that a diagnosis of estrogen dermatitis was highly probable. There have been several reports of this condition since it was first reported as a distinct entity in 1995; but whatever the reasons, the flares were observed only before menstruation in these cases, despite the fact that the serum estrogen levels showed a double-peaked pattern during each menstrual period. This is considered to be a rare case of estrogen dermatitis that flared twice in each menstrual period. Limited improvement was noted in the symptoms even without treatment.