Two patients who developed cutaneous reactions while taking contraceptive hormones are described. In both of these patients the addition of mestranol to in vitro cultures of their peripheral blood lymphocytes resulted in stimulation of lymphoblast formation as measured by the uptake of tritiated thymidine. The eruptions in these cases may represent instances of hypersensitivity to estrogenic components of contraceptive pills.
Savel H, Madison JF, Meeker CI. Cutaneous Eruptions and in Vitro Lymphocyte HypersensitivityAssociated With Oral Contraceptives and Mestranol. Arch Dermatol. 1970;101(2):187-190. doi:10.1001/archderm.1970.04000020057009