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birth defects

Tuesday 3 April 2007

A birth defect is an abnormality of structure, function or metabolism (body chemistry) present at birth that results in physical or mental disabilities or death. Several thousand different birth defects have been identified. Birth defects are the leading cause of death in the first year of life.

About 120,000 babies (1 in 33) in the United States are born each year with birth defects. Both genetic and environmental factors, or a combination of these factors, can cause birth defects. However, the causes of about 70 percent of birth defects are unknown.


- monogenic diseases (single gene defects)
- chromosomal diseases (chomosomal anomalies)
- environmental factors (teratogens)

  • alcohol
  • drugs/medications
  • chemicals

- infectious agents
- multi-factorial birth defects