Familial occurrence of pruritic urticarial papules and plaques of pregnancy

Background: The occurrence of pruritic urticarial papules and plaques of pregnancy (PUPPP) was noted in four women with unusual family relationships. Objective: The purpose of the study was to document the occurrence of PUPPP in these families and to make observations on their possible relevance. Methods: Case reports of the four patients are detailed. Histologic and HLA studies are recorded. Results: In both families, sisters were married to brothers. A common paternal influence is suggested. Conclusion: We postulate that PUPPP may be a maternal response to a circulating paternal factor for which tolerance develops in subsequent pregnancies.