An uninvolved pregnancy in a patient after a previous episode of herpes gestationis

Herpes gestationis is a blistering disease associated with pregnancy that almost invariably recurs in subsequent pregnancies.^1,2 Immunologic factors have been implicated in the pathogenesis of herpes gestationis, and women with HLA-DR₃ and -DR₄ antigens are most at risk.^3,4 Uninvolved pregnancies have been described and were thought to occur in association with a change in paternity.³ It has been suggested that an uninvolved pregnancy may occur if the fetus has the HLA-DR antigens possessed by the mother.¹ We describe a patient whose first pregnancy was complicated by herpes gestationis but whose second was not, despite constant paternity and nonmatching HLA-DR antigens between mother and child.