Nickel contact allergy and menstrual cycle.

According to some reports in the literature, the hormonal fluctuations which occur during the menstrual cycle may affect the clinical expression of contact allergy to a greater or lesser degree. In clinical practice, too, patient history often shows exacerbation of the contact dermatitis during the days immediately preceding menstruation. On the contrary, the follicular phase of the cycle seems to have a temporary protective role in inhibiting the eliciting phase of allergic contact dermatitis.