An estimated 3.3 million children under the age of 5 die each year from serious birth defects, a worldwide report says. But more effective interventions and the use of medical genetic services, especially in poorer countries, could reduce mortality and disability by up to 70%.
"Health policymakers have not been aware of the immense global toll of birth defects, including the true extent of death and disability," concludes the Global Report on Birth Defects. The study examined birth defects in 193 countries and estimated that overall 7.9 million children are born with a serious birth defect of genetic or partially genetic origin—that is, 6% of total births a year worldwide. The study was prepared for the March of Dimes, a US voluntary health group.
About 60% of babies with serious birth defects were born in poor countries, 34% in middle income countries and 6% in rich countries.
The prevalence of all genetic birth defects combined varies between 41.6 per 1000 live births in Austria and 39.7 in France to 82 and 81.3 in Sudan and Saudi Arabia. In the United Kingdom, the rate was 43.8. Aside from poverty, reasons cited for the variation in prevalence between rich and poor nations include frequency of consanguineous marriage (between blood relatives), differences in the percentage of older mothers, and sharp disparities in maternal and child health services.
Arnold Christianson, of the University of Witwatersrand, South Africa, and coauthor of the report, says, "Experience from high income countries shows that overall mortality and disability from birth defects could be reduced by up to 70% if the recommendations of this report were broadly implemented."
The study collected data on single gene disorders, chromosomal disorders, and physical malformations and found the five most serious birth defects of genetic origin in 2001 were congenital heart defects; neural tube defects, haemoglobin disorders, Down’s syndrome (trisomy 21), and glucose-6-phosphate dehydrogenase deficiency. Combined, these five accounted for 25% of all genetic birth defects.
The report also brushes aside the widespread belief that effective intervention and care of birth defects require costly high tech interventions. On the contrary, says the report, effective interventions, including family planning, optimising women’s diets, managing maternal health problems, and avoiding infections, "are both feasible and affordable, even for financially health systems . . . and have proven cost effective where implemented."
The report urges that doctors, nurses, and allied health professionals are trained in the essentials of medical genetics. And it also recommends the implementation of preconception or prenatal genetic screening to identify couples at risk of having a baby with disorders.
Finally, says the report, many risk factors for birth defects such as maternal medical complications, infection, and poor nutrition are common to other maternal and child health problems, and increasing interventions on defects would have wider benefits.
The Global Report on Birth Defects is available at www.marchofdimes.com