Testing For Down Syndrome
Cytogenetic analysis looks at the number and structure of a person's chromosomes. This test, which can be performed on a blood sample, is the test used to definitively determine if an individual has Down syndrome.
|Maternal Age||Risk of Down Syndrome||Total Risk for all Chromosomal Abnormalities|
Prenatal diagnosis for Down syndrome (testing for the condition during pregnancy) is possible. Chromosome studies can be performed on fetal cells collected via chorionic villus sampling (CVS) at ten to twelve weeks of pregnancy or by amniocentesis at fifteen to twenty weeks of pregnancy. Because of the link between the mother's age and the chance of Down syndrome, prenatal diagnosis for Down syndrome and other chromosome conditions is routinely offered to women thirty-five and older. Whether to pursue prenatal diagnosis is a personal decision that can only be made by the parents.
and Gerald L. Feldman
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Pueschel, Siegfried M., ed. A Parent's Guide to Down Syndrome: Toward a Brighter Future, 2nd ed. Baltimore, MD: Paul H. Brooks Publishing, 2001.
Cohen, William I., ed. "Health Care Guidelines for Individuals with Down Syndrome: 1999 Revision." Down Syndrome Quarterly 4, no. 3 (1999): 1-15. <http://www.denison.edu/dsq/health99.shtml>.