Polymorphic eruption of pregnancy (PEP) is a benign, self-limiting, pruritic disorder of pregnancy, which usually affects the primigravida during the last trimester or immediately postpartum. Its pathogenesis is unclear and its clinical manifestations are variable, leading frequently to an incorrect diagnosis. In cases of PEP the histological findings are nonspecific and the laboratory results, including direct immunofluorescence (DIF) and indirect immunofluorescence (IIF), are negative. Polymorphic eruption of pregnancy is not associated with any fetal risk and symptomatic treatment is all that is usually required.

In this review we present the clinical presentation of PEP and a differential diagnosis which defines PEP as a separate entity. We will also review all current data of possible etiologic factors, histologic and immunologic findings, prognosis and therapy.