Prevalence of cleft lip and palate among four provinces in the West and North-West of Iran

BACKGROUND: One of the most common anomalies in newborn infants is cleft lip and/or cleft palate (CL/P). In spite of several studies about the prevalence of this, no investigation evaluated this prevalence in the West and North-West of Iran. With due attention to different ethnic groups in this area, the aim of this study is to investigate whether the distribution of CL/P live births varies regionally in this area of Iran. MATERIALS AND METHODS: A cross-sectional study was conducted using hospital registry records to identify all children born with CL/P. The hospitals with a maternity unit were selected in the capital cities of four provinces in the West and North-West of Iran, East Azarbaijan, Kurdestan, Gilan, and Markazi. The population under study included all infants born alive from 2008 to 2012. RESULTS: During the study period, 107,317 live births were registered in the hospitals with a maternity unit of four cities, and 52 infants (0.485/1000 live births) were born with CL/P. The prevalence in Rasht, Arak, Sanandaj, and Tabriz cities was 0.557, 0.352, 0.503, and 0.559/1000 live births, respectively (P < 0.05), and in cleft types (P < 0.05). Of the 52 infants who were born with CL/P, 24 (46.15%) were girls and 28 (53.85%) were boys (P > 0.05), whereas the prevalence of CL/P based on sex was statistically different among the four provinces (P < 0.05). CONCLUSION: This study shows regional variations in the birth prevalence of clefts and various cleft types. The different effects of gender on the birth prevalence of CL/P from city-to-city may be explained environmentally and/or by genetic factors affecting the development of oral clefts.