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Man with Down syndrome having a check-up.

Man with Down syndrome having a check-up.
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Down syndrome

3-minute read

Down syndrome occurs when a baby is born with an extra (third) copy of chromosome 21. It is a genetic condition and is not an illness or a disease.

Like everyone, people with Down syndrome vary in appearance, ability and personality. But there are some health problems many people with Down syndrome can share.

What causes Down syndrome?

Doctors know how Down syndrome occurs but not why. The body cells of most people have 46 chromosomes.

People with Down syndrome have an extra chromosome 21 in their body cells. Having this extra chromosone happens by chance - not because of anything parents have done.

If you’re pregnant and concerned about having a child with Down syndrome visit Pregnancy, Birth and Baby for more information on Down syndrome screening and diagnosis.

Health problems for people with Down syndrome

If you have Down syndrome, you may have a higher chance of some health problems than other people. You may also have lower immunity. This means you may get sick more often especially in early childhood.

People with Down syndrome have a higher risk of problems seeing or hearing. They may also have gut or heart defects, hypothyroidism, or problems with their bones.

Everyone with Down syndrome has some degree of learning difficulty. You may need speech and language therapy to help you speak clearly.

A healthy diet and physical activity are important for everyone including people with Down syndrome. You have a higher risk than other people of:

Regular checks may be required for health problems including your teeth development.

There are many people with Down syndrome who are happy, healthy and leading independent lives but you may need more support to help you achieve the kind of life that most people take for granted.

Watch this video about the importance of building relationships with health professionals for people with Down syndrome and their families.

More information

If you have Down syndrome or you are caring for someone with Down syndrome, speak to your doctor about any particular health concerns you have or require more information about.

You can also visit Down Syndrome Australia to find resources to help you with your health, education and employment. There are also organisations that you can contact in your state or territory:

Support for carers

Are you caring for someone with Down syndrome? Find practical information and useful resources for carers on Carer Gateway. You can also learn more about carers' support and services in your state or territory through Carers Australia.

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Last reviewed: February 2018

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