Updating the epidemiology of cleft lip with or without cleft palate.

BACKGROUND: Much of the literature on the epidemiology of cleft lip with or without cleft palate is more than three decades old. The question arose as to whether there has been any recent change or trend in its rate of occurrence.

METHODS: The number of live births with cleft lip or other congenital anomalies was solicited from national and international organizations. Data were collected for 34 states and 30 countries for the years 2002 to 2006. All data were normalized and reported per 10,000 live births. Descriptive statistics, in addition to correlation and regression, were used to analyze the data.

RESULTS: Data for the 5-year period demonstrated that the overall congenital anomaly rate increased in the United States and decreased internationally. The states with the highest and lowest rates were Maryland (21.46) and West Virginia (2.59), respectively. The United States cleft lip national rate averaged 7.75. Countries with the highest and lowest rates were Japan (19.05) and South Africa (3.13), respectively. Internationally, the rate of cleft lip declined, with an average overall prevalence of 7.94.

CONCLUSIONS: The average prevalence of cleft lip with or without cleft palate was 7.75 per 10,000 live births in the United States and 7.94 per 10,000 live births internationally. The trends diverged over the 5-year period, as the rate was stable in the United States and the international rate declined.