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Is Down syndrome a disappearing birth defect?
Veronica R Collins1, Evelyne E Muggli, Merilyn Riley
1Public Health Genetics, Murdoch Childrens Research Institute, Royal Children's Hospital, Victoria, Australia. veronica.collins@mcri.edu.au
The Journal of Pediatrics
|December 25, 2007
Summary
The prevalence of Down syndrome (DS) increased in Victoria, Australia, between 1986 and 2004, particularly in women under 35. Prenatal diagnosis rates rose significantly, highlighting the need for ongoing support services for individuals with DS.
Area of Science:
- Medical Science
- Genetics
- Public Health
Background:
- Down syndrome (DS) is a genetic disorder associated with intellectual disability and developmental delays.
- Understanding trends in DS prevalence is crucial for public health planning and resource allocation.
Purpose of the Study:
- To analyze the prevalence of Down syndrome (DS) in Victoria, Australia, from 1986 to 2004.
- To identify demographic and temporal trends in DS diagnoses.
Main Methods:
- Data linkage between the Victorian Birth Defects Register and the Prenatal Diagnosis Database.
- Calculation of annual total and birth prevalence estimates for DS.
- Presentation of data using 3-year moving averages.
Main Results:
- Total DS cases increased from 113 (1986) to 188 (2004).
- Prevalence in women under 35 rose from 10/10,000 to 12.5/10,000; in older women, it increased from 70/10,000 to 90/10,000.
- Prenatal diagnosis proportion increased from 3% to 60% in younger women.
Conclusions:
- The study highlights an increasing trend in Down syndrome prevalence.
- Findings underscore the ongoing need for resources and support systems for individuals with DS and their families.
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