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What is Down Syndrome?

Down syndrome, also called Trisomy 21, is a condition in which the presence of an extra chromosome causes differences (often delays) in the way a child develops, both mentally and physically. It affects about 1 in every 800 babies.


At the time of conception, most babies receives 46 chromosomes: 23 from the mother and 23 from the father. In most cases of Down syndrome, a child gets an extra chromosome 21 - for a total of 47 chromosomes instead of 46. It's this chromosome that causes the physical features and developmental characteristics associated with Down syndrome.

No one knows for certain why Down syndrome occurs, although women age 35 and older have a significantly higher risk of having a child with Down syndrome. At age 30, a woman has about a 1 in 900 chance of conceiving a child with Down syndrome; by age 35, the number is 1 in 350. By 40 the risk rises to about 1 in 100.

Medical Issues:

The health problems that accompany Down syndrome can be treated, as they should be for any child. The medical problems that have been associated with Down syndrome vary widely from child to child. Good regular check ups with a respectful physician will maximize each child's health. Seek a physician who sees the potential in your child and will give him/her every opportunity to be healthy and productive.

How Down Syndrome Affects Kids:

Children with Down syndrome will share physical features of the parents and siblings; there may also be a tendency to have certain physical features such as a flat facial profile, a slight slant to the eyes, small ears, and short stature.

Low muscle tone is also characteristic of children with Down syndrome. Though this can and often does improve over time, most children typically reach developmental milestones - like sitting up, crawling, and walking - later than other kids.

Most babies with Down syndrome are born average in length and weight, but many grow at a slower rate and remain smaller than their peers. Height challenged!

During infancy, low muscle tone may contribute to sucking and feeding problems and other digestive issues. Occupational and physical therapists work with infants to improve muscle tone and mitigate the impact of this challenge.

Toddlers and older kids may have delays in speech and self-care skills like feeding, dressing, and toilet teaching. Both speech therapy and occupational therapy; privately or through the schools, will help tremendously to minimize impact in these areas.

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