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Racial/ethnic differences in the birth prevalence of spina bifida - United States, 1995-2005
In 1992, the U.S. Public Health Service recommended that all women of childbearing age consume 400 microg of folic acid daily to help prevent pregnancies affected by neural tube defects (NTDs) such as spina bifida. Subsequently, the Food and Drug Administration mandated adding folic acid to all enriched cereal grain products by January 1998. During October 1998--December 1999, the birth prevalence of spina bifida in the United States decreased 22.9% compared with 1995--1996; however, by 2003--2004, no further decrease had been observed. Notably, the prevalence of NTD-affected pregnancies remained higher among Hispanic women than among women in other racial/ethnic populations. To update previously reported data and assess racial/ethnic differences, CDC analyzed birth certificate data for four periods during 1995--2005. This report summarizes the results of that analysis, which indicated that from the early postfortification period, 1999--2000, to the most recent period of analysis, 2003--2005, the prevalence of spina bifida declined 6.9%, from 2.04 to 1.90 per 10,000 live births (prevalence ratio [PR] = 0.93; 95% confidence interval [CI] = 0.87--1.00). Among infants with non-Hispanic black mothers, prevalence fell 19.8%, from 2.17 to 1.74 per 10,000 live births (PR = 0.80; CI = 0.67--0.96), while prevalence among infants with non-Hispanic white and Hispanic mothers remained nearly constant. Additional public health efforts targeting women with known risk factors (e.g., obesity and certain genetic factors) likely are needed to further reduce the prevalence of spina bifida in the United States.
In 1992, the U.S. Public Health Service recommended that all women of childbearing age consume 400 microg of folic acid daily to help prevent pregnancies affected by neural tube defects (NTDs) such as spina bifida. Subsequently, the Food and Drug Administration mandated adding folic acid to all enriched cereal grain products by January 1998. During October 1998--December 1999, the birth prevalence of spina bifida in the United States decreased 22.9% compared with 1995--1996; however, by 2003--2004, no further decrease had been observed. Notably, the prevalence of NTD-affected pregnancies remained higher among Hispanic women than among women in other racial/ethnic populations. To update previously reported data and assess racial/ethnic differences, CDC analyzed birth certificate data for four periods during 1995--2005. This report summarizes the results of that analysis, which indicated that from the early postfortification period, 1999--2000, to the most recent period of analysis, 2003--2005, the prevalence of spina bifida declined 6.9%, from 2.04 to 1.90 per 10,000 live births (prevalence ratio [PR] = 0.93; 95% confidence interval [CI] = 0.87--1.00). Among infants with non-Hispanic black mothers, prevalence fell 19.8%, from 2.17 to 1.74 per 10,000 live births (PR = 0.80; CI = 0.67--0.96), while prevalence among infants with non-Hispanic white and Hispanic mothers remained nearly constant. Additional public health efforts targeting women with known risk factors (e.g., obesity and certain genetic factors) likely are needed to further reduce the prevalence of spina bifida in the United States.
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