The database prepared for the March of Dimes report details the prevalence rates and the numbers of affected births in 193 countries. The data collected include information on single-gene disorders, chromosomal disorders, and physical malformations.
The data do not allow for precise comparisons of birth defects prevalence among countries, according to its authors, Arnold Christianson, M.D., of the National Health Laboratory Service and University of the Witwatersrand, Johannesburg, South Africa; Bernadette Modell, M.D., Ph.D. of the Royal Free and University College Medical School, London, England; and Christopher P. Howson, Ph.D., vice president for Global Programs at the March of Dimes.
"Valid detailed comparisons among countries must await the collection of additional empirical data on birth prevalence," says Prof. Modell.
The data, however, do permit broad comparison of specific birth defects across regions and among countries of different income level, Dr. Howson says. "Such comparisons show that the highest birth defects prevalence is found among the world's poorest countries, whereas many of the lowest rates are found among the world's wealthier countries."
Worldwide, the birth prevalence of all genetic birth defects combined range from a high of 82 per 1,000 live births in low-income regions to a low of 39.7 per 1,000 live births in high-income regions.
Five common birth defects of genetic or partially genetic origin co
Source:March of Dimes Birth Defects Foundation