General Facts

The following is a compiled list of facts I found interesting, while researching about Down Syndrome on various websites.  I think the information is interesting and informative.


*Down Syndrome occurs when an individuals DNA has three chromosomes instead of two copies of the 21st chromosome.

*March 21st is World Down Syndrome Day- represents 3 copies of the 21st chromosome.

*Women of any age have the possibility of having a child with Down Syndrome, however women older than 35 have a higher risk (1 in 350 chance) of having a child with Down Syndrome; 40 year old women have a 1 in 100 chance, and women over 45 have a 1 in 30 chance.

*One in every 691 babies born has Down Syndrome

*There are approximately 6,000 babies born each year in the United States

*Total population 400,000 people with Down Syndrome living in the United States

*The typical lifespan for individuals affected is 50-55 years

*Men with Down Syndrome are uniformly sterile, therefore, unable to reproduce.

*Women with Down Syndrome are fully capable of having children. In addition there is a 50% chance that a baby born to a mother with Down Syndrome will have the chromosome defect as well.

Physical Defects:
*50% of Down Syndrome children are born with a heart defect; most commonly the individual has a hole between two sides of the heart.

*Hirshprung Disease (congenital aganglionic megacolon) causes an intestinal obstruction; this disease more commonly occurs in children with Down Syndrome than in other children.

Most common features in appearance of Down Syndrome at birth include: (from the online medical dictionary)

*Slight flattening of the face
*Minimal squaring off at the top of the ears
*A low bridge of the nose
*An epicentral fold (fold of skin over the top of the inner corner of the eye)
*A narrowing of the palate