Razi Journal of Medical Sciences

    Background & Aim: Consanguineous marriage is strongly favored in many large human populations. In most parts of South Asia, consanguineous marriage accounts for 20-50% of the total present generation. The effect of consanguinity on hereditary deafness has been well studied and documented. Many authors have suggested that approximately one half of sensory neural hearing loss in children can be attributed to hereditary causes. The aim of this research is to evaluate the prevalence of consanguineous marriage in children with SNHL. Patients & Method: This research was carried out in rehabilitation centers of welfare organization in seven provinces of Iran. 1352 infants and preschool children with SNHL participated in this study. To collect data, participants were asked to fill out questionnaires including personal history, medical history, and hearing loss history. Results: Consanguinity was found among 45.7% of children whose parents were first cousins and 17.2% of children whose parents were second cousins. Hereditary factors were thought to be the cause of bilateral SNHL in 863 children(62.9%). Conclusion: The incidence of hereditary hearing impairment is very high in developing countries compared to developed ones. Prevention seems essential to reduce the incidence of genetic hearing loss. Consanguinity should be discouraged and genetic counseling is to be applied at least for those at risk of developing genetic diseases including hearing impairment.