Overall, the weight of evidence is that no significant relationship can be found between the physical characteristics and the person's mental functioning.
Cliff Cunningham, Understanding Down Syndrome: An Introduction for Parents
How did the doctors know my baby had Down syndrome?
Many babies with Down syndrome have certain physical characteristics which are common in Down syndrome. These signs occur in up to 80% of all cases. Individual characteristics are often found in children without Down syndrome but the Down syndrome child will have several. These traits are:
- the eyes have an upward and outward slant
- there is a fold of skin on the inner side of the eye (epicanthal fold)
- the eye slit is narrow and short
- small, white patches can be seen on the edge of the iris
- the face has a flat appearance
- the head is smaller than average
- the soft spots on the head (fontanels) are larger than normal because the baby is growing more slowly
- the ears are smaller and lower-set
- the mouth is small and the lips are thin which leads to the tongue sticking out because the inside of the mouth is smaller
- the neck appears slightly short and loose folds of skin are seen at the back and sides (these go away as the baby grows)
- the legs and arms are short in relation to the body
- the hands are broad and flat with short fingers, the little finger slants inward, and there is a single crease across the palm
- the feet are broad with short toes and there is a larger space than normal between the big toe and the other toes
- there is poor muscle tone (hypotonia) and loose-jointedness (hyperflexibility)
- reflexes tend to be weaker and the cry is weak
If a child has six to ten of these signs, the doctor can be almost certain that the child has Down syndrome.
What effect will these physical characteristics have on my baby's health?
Children with Down syndrome can be prone to breathing problems due to the smallness of the mouth and the poor development of the sinuses. This can lead to mouth breathing which will encourage the protruding tongue often seen in children with Down syndrome. The protruding tongue in combination with low muscle tone in the muscles of the face can cause nursing problems since the child with Down syndrome may have trouble getting a tight seal on a nipple. The baby may also have a weak suck due to hypotonia and may later have trouble eating solid foods. A therapist can help with this problem.
What is hypotonia?
Low muscle tone or hypotonia, is very common in children with Down syndrome. Their muscles feel floppy. Although the degree of hypotonia varies from child to child, it generally affects all muscles in the body. Hypotonia may contribute to delays in motor development but with the help of a therapist, improvement in your baby's motor skills will be achieved. Therapy for hypotonia should begin within the first few weeks after the baby is born. A therapist can show you techniques (such as holding the baby in a certain way) that can be beneficial to your baby's development. Low muscle tone can effect eating and speaking skills so a speech therapist should work with your baby. Hyperextensible joints can also effect your baby's development. Your baby's joints may be very flexible. This flexibility can make it difficult for your baby to be stable enough to learn how to walk. Professionals such as Occupational and Physical Therapists can help alleviate these problems. Early intervention is the key.