Some Facts About Down Syndrome

Down syndrome, a chromosomal abnormality, is the most common cause of mental retardation. Some facts about it:

* One in 800 to 1,000 people are born with the condition.

* Children with Down syndrome run a higher risk of heart defects, visual or hearing impairment, and other health problems.

* The average age at which people with Down syndrome die rose from 25 in 1983 to 49 in 1997, according to the U.S. Centers for Disease Control and Prevention. Other studies put life expectancy at over 55.

* Most individuals with Down syndrome have IQs in the mild to moderate range of mental retardation.

* In the United States, about 350,000 families are affected by Down syndrome.

* Women age 35 and older have an increased risk of having a child with Down syndrome. A 35-year-old woman has a one in 400 chance of conceiving a child with Down syndrome; the odds increase to one in 110 by age 40.