A generalized eruption, characterized by widely scattered, intensely itching, erythematous papules, that occur only during pregnancy is described. Among the 12 patients reported, there were 37 previous pregnancies, with fetal loss in 10 (27%). However, with corticosteroid therapy, in 11 cases there was no fetal loss; one stillbirth occurred in a patient treated only with progesterone. Biochemical changes associated with the dermatitis included elevated urinary chorionic gonodotropin during the last trimester, lowered plasma hydrocortisone level, and shortened hydrocortisone half-life.