An infant with hydrometrocolpos, secondary to vaginal atresia, and bilateral polydactyly, the product of unaffected first cousin parents, is presented. Autosomal recessive inheritance for hydrometrocolpos secondary to vaginal atresia is suggested by this case and by a previous report of two sibships each with affected sisters and each issuing from consanguineous parents. A review of the literature reveals the association of hydrometrocolpos, secondary to vaginal atresia, with polydactyly in four additional cases. Early diagnosis and treatment of hydrometrocolpos is emphasized.