Polymorphic eruption of pregnancy (Q45224)

Polymorphic eruption of pregnancy is a dermatosis which occurs almost exclusively in primigravidae or women with multiple pregnancy. It is associated with above average weight gain in pregnancy and it is thought that distension of abdominal skin is important in the pathogenesis: the precise mechanism is not understood. The eruption characteristically first appears in the third trimester of pregnancy as intensely itchy erythematous urticarial papules and plaques in and around the abdominal striae distensae. In some women it may then become more generalised. Onset is sometimes delayed until the immediate postpartum period. It does not usually recur in subsequent pregnancies.