Symptoms
By Mayo Clinic staffChildren with Down syndrome have a distinct facial appearance. Though not all children with Down syndrome have the same features, some of the more common features are:
- Flattened facial features
- Small head
- Short neck
- Protruding tongue
- Upward slanting eyes, unusual for the child's ethnic group
- Unusually shaped ears
Children with Down syndrome may also have:
- Poor muscle tone
- Broad, short hands with a single crease in the palm
- Relatively short fingers
- Excessive flexibility
Infants with Down syndrome may be of average size, but typically they grow slowly and remain shorter than other children of similar age. In general, developmental milestones, such as sitting and crawling, occur at about twice the age of children without impairment. Children with Down syndrome also have some degree of mental retardation, most often in the mild to moderate range.
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