Obstructive Sleep Apnoea (OSA) is a medical condition that involves breathing difficulties in children (or adults) when they’re asleep. It happens as they sleep, when their muscles relax and causes their airway to become partly or totally blocked.

A common cause of OSA in all children are enlarged tonsils and adenoids which grow most quickly between the ages of 2 and 7. About three-quarters of children with Down syndrome are diagnosed with OSA. It can be mild, moderate or severe.

Early diagnosis and treatment are key to prevent complications.

Signs and symptoms

If your child has OSA you may notice:

  • snoring, or short pauses or gasps in breathing during sleep, for the whole night or at intervals
  • breathing through the mouth rather than the nose
  • enlarged adenoids and tonsils in the back of their throat
  • restless, disturbed sleep
  • sweating
  • bed wetting
  • daytime sleepiness.

It’s common for any child with OSA to feel tired during the day and find it difficult to pay attention, and some children can have trouble learning or show behavioural problems.

It can affect their everyday function, language development and lead to other medical conditions in children with Down syndrome.

What causes OSA in children with Down syndrome?

It can be caused by the physical features children have, such as:

  • narrow upper airways
  • larger tongues
  • flattened mid-face (particularly the bridge of their nose)
  • smaller upper jaw
  • downward displacement of their tongue

Children can also have hypotonia, which is a medical term for poor muscle tone, where the muscles don’t fully relax and have a certain amount of tension or stiffness. They may also be prone to obesity, which increases the risk of heart disease, and can cause OSA or make it worse.

If your child has a heart condition or pulmonary hypertension, OSA can increase the stress to their heart, so it’s important to monitor your child’s sleep regularly and talk to your doctor about any concerns you may have.

How is OSA diagnosed?

Early diagnosis is key to treatment and to prevent complications. If you think your child may have OSA, visit your GP, who can refer your child to a sleep physician who may recommend a formal sleep study. A sleep physician will discuss the need for this with you and determine if it’s what your child needs.

It’s helpful to keep a record of any sleep issues and your child’s sleep patterns in a sleep diary. You may choose to video your child sleeping, as this can be useful when discussing your child’s sleep symptoms.


Once a diagnosis has been made, treatment depends on what is causing the problem and how serious it is.

Some children who have enlarged adenoids and tonsils may have surgery to take them out. Other children with special conditions may need a Continuous Positive Airways Pressure (CPAP) machine to help them breathe at night.

Your doctor will discuss the treatment options with you and what the best approach is for your child.

Some children with Down syndrome may continue to have symptoms even after a treatment happens. Your child may need further therapy.

Key points

  • Early diagnosis and treatment are key to prevent complications.
  • Treatment depends on what is causing the problem, how serious it is and any other pre-existing health conditions
  • Regularly monitor your child’s sleep patterns, even after a treatment, as symptoms can reoccur.

More information

Developed by Department of Respiratory and Sleep, Queensland Children’s Hospital. We acknowledge the input of consumers and carers.

Resource ID: FS037. Reviewed: June 2021.

Disclaimer: This information has been produced by healthcare professionals as a guideline only and is intended to support, not replace, discussion with your child’s doctor or healthcare professionals. Information is updated regularly, so please check you are referring to the most recent version. Seek medical advice, as appropriate, for concerns regarding your child’s health.

Last updated: October 2023