Population Statistics

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Population Statistics

How many people in Australia have Down syndrome?

There is no national data describing the prevalence and demographics of people with Down syndrome in Australia.

The best estimate available is that there are between 13,000-15,000 individuals with Down syndrome in Australia as of 2019. This estimate is based on Western Australia data and applying these numbers to the Australian population.  

Recent 2021 NDIS participant data supports this estimate, keeping in mind that not all people with Down syndrome will be NDIS participants (see our NDIS Statistics page).

These population figures mean that for every 10,000 people there are 5.14 people with Down syndrome. This is similar to other countries like the UK.


Down syndrome is the most commonly occurring chromosomal condition. Between 2016 and 2020, there were an estimated 265 births of babies with Down syndrome per year. This means around 1 in every 1,158 babies born in Australia will have Down syndrome.

The incidence of births of children with Down syndrome increases with the age of the mother. The chance of a woman conceiving a child with Down syndrome varies from 1 in 1400 for a woman 20 years of age to 1 in 30 at age 45 years. However, younger women have babies more frequently, so the majority of babies born with Down syndrome are born to women under 35 years of age.


  1. de Graaf G., Skladzien E., Buckley F., Skotko B. G. (2022). Estimation of the number of people with Down syndrome in Australia and New Zealand. Genetics in Medicine. Published online: October 03, 2022. doi:10.1016/j.gim.2022.08.029
  2. Australian Institute of Health and Welfare (2021). Australia’s mothers and babies, Web report. https://www.aihw.gov.au/reports/mothers-babies/australias-mothers-babies/contents/about

Last updated: June 2023