Chromosomal abnormalities

Sometimes there is a problem when the chromosomes are formed. This is called a chromosomal abnormality, also known as a genetic disorder. There are three groups of chromosomal abnormalities:

1. There is an extra chromosome: one too many.
2. There is an extra part of a chromosome.
3. There is a missing part of a chromosome.

A chromosomal abnormality cannot be cured. The child may have intellectual disabilities and one or more physical defects as a result.

Down syndrome

Someone with Down syndrome has an extra chromosome 21 (trisomy 21). A child born with Down syndrome will have it for the rest of their life. People with Down syndrome have an intellectual disability. It is more severe in some people than in others. It is impossible to predict this beforehand.

Development opportunities

Children with Down syndrome learn more slowly than children without Down syndrome.  It takes them longer to learn how to talk, walk, or swim, for example. But eventually many children with Down syndrome can do these things too. People with very severe intellectual disabilities have fewer development opportunities. For instance, many of them only learn to talk a little.

Physical problems

People with Down syndrome are more likely to have physical health problems. Almost half of these children are born with a heart defect. Usually, this does not cause them any problems. Half of these children with a heart defect will need surgery in the first few months of their lives. After that, they usually no longer have any problems.

Children with Down syndrome may also have a gastrointestinal abnormality (problems with their stomach or intestines). They can also have surgery for this. 

Other physical problems that are common in children with Down syndrome can affect:

• the respiratory system (airways)
• hearing
• vision (eyes)
• speech
• immune system (resistance to infections).

These problems are more severe in some children than in others.

Life expectancy

In the past, people with Down syndrome often died at a young age. Care for people with Down syndrome is now much better than it used to be.  They are more likely to be able to receive treatment for the conditions they have. As a result, they are in better health. However, children with Down syndrome on Bonaire, St Eustatius, and Saba cannot receive all the care they need. If extra care is needed, they must go to another island or a different country. 

Adults with Down syndrome are more likely than average to develop a form of dementia (Alzheimer’s disease). They often develop this at a younger age than average. On average, people with Down syndrome now live to be 60 years old.

Support

Your midwife can refer you to other care providers for guidance and support.

Child with Down syndrome more likely in older pregnancy

The older the pregnant person, the greater the chance of having a child with Down syndrome.

How to read the table

If 10,000 people are pregnant at the age of 20 years, 11 of them are pregnant with a child with Down syndrome. The other 9,989 women are pregnant with a child without Down syndrome.

If 10,000 people are pregnant at the age of 45 years, 615 of them are pregnant with a child with Down syndrome. The other 9,385 women are pregnant with a child without Down syndrome.

Edwards syndrome and Patau syndrome

Someone with Edwards syndrome has an extra chromosome 18 (trisomy 18).  Someone with Patau syndrome has an extra chromosome 13 (trisomy 13). Edwards syndrome and Patau syndrome are very serious conditions. These conditions develop early in pregnancy and cannot be cured. Children with Edwards syndrome or Patau syndrome have very poor health. These children are often ill due to abnormalities of the heart and other organs. They also frequently suffer from infections. Most of these children die during pregnancy or shortly after birth.

Life expectancy

About 1 in 10 to 20 children born alive with Edwards syndrome live beyond the age of 1 year old.

Approximately 1 or 2 in 10 to 20 children born alive with Patau syndrome live beyond the age of 1 year old.

Health

Children with Edwards syndrome or Patau syndrome have many health problems.

Edwards syndrome:

• At birth, children are almost always too small and too lightweight.
• Their brains are not fully developed. As a result, these children are usually severely disabled.
• They often have a serious heart defect.
• They also often have abnormalities in other organs.
• They often have breathing problems and a high risk of pneumonia.
• They have severe problems with swallowing, eating, and drinking.

Patau syndrome:

• They often have a serious heart defect.
• Their brains are not fully developed. This causes severe disability and often epilepsy.
• They have difficulty breathing, and easily catch pneumonia.

Physical characteristics

Edwards syndrome:

• small head
• small jaw
• overlapping fingers
• club feet
• heart defects

Patau syndrome:

• small head
• abnormalities of the nose and eyes
• cleft palate
• extra finger or toe
• heart and brain abnormalities

A missing or extra part of a chromosome

Sometimes a child has a piece of a chromosome missing, or an extra part too many.  This is usually a serious genetic disorder. The child may have intellectual disabilities and one or more physical defects as a result.