Birth prevalence of cleft lip and palate in Colorado by sex distribution, seasonality, race/ethnicity, and geographic variation

Abstract

An epidemiologic study was designed to describe the association of potential risk factors with the occurrence of cleft lip and palate (CL/P) births in Colorado for the years 1982-1988. There were 307 children out of 381,175 live births identified, through birth certificate data, with a diagnosis of cleft palate or cleft lip with or without cleft palate. For this period, the birth prevalence was 0.81/1000. Male gender [odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.28, 2.04], white race (OR = 2.87, 95% CI = 1.52, 5.44), and non-metropolitan residence (OR = 1.59, 95% CI = 1.23, 2.05) were each associated with an excess risk of having a cleft abnormality of any type at birth. No differences in the occurrence of cleft lip and palate were observed by month of birth, altitude of county of residence, or in Hispanic compared with non-Hispanic newborns. Using information from the 1989 Colorado Registry for Children with Special Needs, there was little evidence of ascertainment bias on major factors of interest for the birth certificate data. Further studies are required to define the factors associated with excess risk of CL/P in non-metropolitan areas.