Down syndrome occurs when an abnormality takes place during the process of cell division, which leads to the production of an extra copy of chromosome 21. As these Down syndrome statistics would soon show you, that additional genetic material causes several changes that affect a person’s physical features and intellectual development.
Down syndrome is a genetic disorder that has no known cure and prevention. It’s the most common chromosomal disorder globally and affects people of all ethnic groups and sexes.
This article contains a compilation of the most relevant statistics and facts on Down syndrome. Dive in to learn more interesting facts on abortion rates, risk factors, effects of Down syndrome, etc.
Top 10 Down Syndrome Statistics and Facts
- Down syndrome affects about 6 million people worldwide.
- Trisomy 21 accounts for 95% of all Down syndrome cases.
- Only 1% of all Down syndrome cases are hereditary.
- Children with Down syndrome have an increased risk of hearing and vision problems.
- The average lifespan of a person with Down syndrome is 60 years.
- About 50% of women with Down Syndrome are fertile.
- African Americans with Down syndrome have a shorter lifespan than their white counterparts
- 1 out of 700 babies born in the United States has Down syndrome.
- In Iceland, nearly 100% of women who receive positive tests for Down syndrome terminate their pregnancy.
- In India, approximately 29,000 babies are born with Down syndrome each year.
Fascinating Facts and Statistics on Down Syndrome
1. Down syndrome affects about 6 million people worldwide.
The World Health Organization (WHO) reports that 1 in every 1,000–1,100 babies is born with Down syndrome worldwide.
2. Down syndrome is named after Dr. John Langdon Down.
In 1866, English doctor John Langdon Down became the first person to describe Down syndrome fully.
However, Down syndrome facts show that its genetic cause was discovered in 1959 by the French physician, Jérôme Lejeune.
3. World Down Syndrome Day is on March 21st.
March 21st was chosen to depict the triplication of chromosome 21 that causes Down syndrome.
4. Trisomy 21 accounts for 95% of all Down syndrome cases.
Translocation makes up 4% of all cases. Mosaicism, on the other hand, is the least common form of Down syndrome. It accounts for just 1% of all cases, according to the mosaic Down syndrome facts.
5. Only 1% of all Down syndrome cases are hereditary.
Research shows that one-third of all Down syndrome cases resulting from translocation are hereditary. However, heredity is not a factor in trisomy 21 and mosaicism.
6. Chances of having a second child with translocation Down syndrome are roughly 15% if the mother is a carrier.
Down syndrome’s recurrence is 10–15% if the mother is the carrier of the genes and 3% if the father carries them.
7. People with Down syndrome have distinct physical features.
While these features may vary, people with Down syndrome tend to have a flattened face, small ears, short neck, height, loose joints, and a tongue that sticks out of the mouth.
8. Children with Down syndrome have an increased risk of developing hearing and vision problems.
Down syndrome statistics reveal that 75% of children who have it might develop hearing loss, and about 60% may suffer from eye diseases such as cataracts.
Also, 50% of children with Down syndrome are born with congenital heart defects.
9. Individuals with Down syndrome have an average IQ of around 60.
(Henry Spink Foundation)
While some persons have been observed to have an IQ as high as 120, the average still revolves between 50–60, and it’s lower than in individuals without Down syndrome.
10. The average lifespan of a person with Down syndrome is 60 years.
(Global Down Syndrome Foundation)
The Down syndrome life expectancy statistics indicate a significant increase from just 25 years in 1983 to 60 years today. This dramatic increase is mostly due to the end of inhumane abuse and discrimination against people with Down syndrome.
11. Around 30% of patients with Down syndrome die in their first 12 months of life.
The Down syndrome stats show that the most prevalent causes of early mortality in patients with this condition are respiratory infections and congenital heart disease.
12. One in 200 women has a miscarriage caused by amniocentesis.
Amniocenteses is the Down syndrome test for high-risk pregnancies, and it carries a 0.5–1% risk of miscarriage.
Statistics show that roughly 24% of pregnancies end in a miscarriage or stillbirth caused by amniocenteses, increasing the Down syndrome mortality rate.
13. Adopting a child with Down syndrome can cost as much as $20,000.
Special needs adoption fees range anywhere between $15,000–$20,000. Some adoption fees could also include extra charges for travel or medical expenses.
Down Syndrome Demographics: Statistics and Facts
14. There are slightly more males with Down syndrome than females.
Research shows that there is a 1.15:1 male-to-female ratio among people with Down syndrome.
However, the Down syndrome facts and statistics show that this only occurs in infants with free trisomy 21.
15. About half of women with Down syndrome are infertile.
Research points out that 15-30% of women with trisomy 21 are fertile and have approximately 50% risk of having children with trisomy 21. However, males are known to be infertile due to defective spermatogenesis.
16. Women over 35 are more likely to have a baby with Down syndrome.
Based on the Down syndrome statistics by age, a 40-year-old woman has roughly one in 100 chances of having a child with Down syndrome. However, due to the higher birth rate in younger women, 80% of children with Down syndrome are born to women younger than 35.
17. Roughly half of the people living with Down syndrome will develop memory problems by their 50s.
The statistics on down syndrome show that people with the condition develop problems with thinking and memory as they grow older. Moreover, around 50% of them will develop Alzheimer’s disease.
18. African Americans with Down syndrome have a shorter lifespan than their white counterparts.
14-year research involving nearly 18,000 participants in the US revealed that white people with Down syndrome have a life expectancy of 50. This is significantly higher compared to that of 25 years for African Americans and 10 for other races.
19. A 4-year study revealed that cases of Trisomy 21 were the most prevalent in Alaska Natives.
(March of Dimes)
A 2012–2016 study showed that Down syndrome occurred in 35.1 of every 10,000 American Indian live births. Asians had the lowest rate—9.5 of every 10,000 live births.
Down Syndrome Statistics By Country
20. Around 1 in 700 babies born in the US have Down syndrome.
Statistics indicate that roughly 6,000 babies born in the US each year have Down syndrome. This makes it the most prevalent chromosomal disorder in the US.
21. In the US, 67% of pregnancies that test positive for Down syndrome are terminated.
The Down syndrome abortion statistics indicate that Denmark has a termination rate of 98%, United Kingdom 90%, and France 77%.
22. 57% of adults with Down syndrome in the United States are employed.
A 2015 survey that involved 511 participants with Down syndrome revealed that 30% of them were unemployed, 26% were volunteers, and 3% were self-employed.
23. In Iceland, nearly all women who receive positive tests for Down syndrome terminate their pregnancy.
When it comes to Iceland, its Down syndrome statistics show that the country has an average of just two children born with the disorder each year. This is probably due to the introduction of prenatal screening in 2000.
24. Down syndrome accounts for 8% of all congenital abnormalities in Europe.
(EU Science Hub)
Each year, 104,000 children in the countries of the EU are born with congenital abnormalities. In these countries, Down syndrome occurs at a rate of about 1 in 600–1000 births.
25. There are roughly 15,000 people with Down syndrome in Australia.
(Down Syndrome Australia)
The Down syndrome statistics from 2019 indicate that one in every 1,100 babies born in Australia has Down syndrome. Based on this data, 290 babies are born with Down syndrome in the country every year.
26. Approximately 45,000 Canadians have Down syndrome.
Every year, an estimated one in 781 babies is born with Down syndrome in Canada.
27. Over 2 million people in China have Down syndrome.
When it comes to the number of Chinese babies born with Down syndrome, the statistics show that one in 700 babies in the country are diagnosed with the condition at birth.
However, Down syndrome is disappearing in China, as 95% of the women baring babies with the condition decide to terminate their pregnancies.
28. In India, approximately 32,000 babies are born with Down syndrome every year.
(Down Syndrome Prenatal Testing)
This is due to the lack of Down Syndrome awareness and adequate medical facilities.
29. In Japan, approximately 2,200 babies are born with Down syndrome every year.
(Wiley Online Library)
However, this figure is expected to reduce, as prenatal screenings are gaining popularity.
Roughly 90% of women choose to abort because of the disorder, as supported by the recent Down syndrome pregnancy termination statistics.
30. In South Africa, Down syndrome is more prevalent in rural than in urban areas.
(Scielo South Africa)
Research shows that the occurrence of Down syndrome in South Africa is very high, and it occurs at a rate of 1.33 to 1.8 per 1,000 live births in urban areas and 2.1 per 1,000 births in rural areas.
What causes Down syndrome?
Down syndrome is a common genetic disorder that occurs when an abnormal cell division leads to creating a full or partial copy of chromosome 21. This extra copy leads to several physical changes and intellectual difficulties.
How is Down syndrome diagnosed?
Down syndrome can be diagnosed during pregnancy or after birth. Doctors use a combination of ultrasounds and blood tests to determine the likelihood of Down syndrome during pregnancy. The blood tests measure hormone and protein levels, while the ultrasound checks for changes in physical features.
Diagnostic tests such as chorionic villus sampling and amniocentesis are carried out based on the screening results. Chorionic villus sampling involves removing a small biopsy of the placenta for genetic testing, and amniocentesis involves inserting a needle into the amniotic sac surrounding the fetus.
How long do people with Down syndrome live?
People with Down syndrome have a significantly increased life expectancy—from 25 years in 1983 to 60 years today.
Depending on the severity of their health problems, a lot of individuals live into their 80s. This is mostly due to increased awareness and decreased discrimination towards people with Down syndrome.
Do scientists know how to prevent Down syndrome?
Currently, there is no way to prevent Down syndrome. However, some prenatal tests and screenings could predict whether a baby has Down syndrome or not.
A genetic counselor can also determine if you have a high chance of having a baby with Down syndrome. It is best to consult with your genetic counselor to understand your options.
How many people have Down syndrome?
Down syndrome remains the most commonly occurring chromosomal condition in the world. According to the WHO, out of every 1,000 or 1,100 babies worldwide are born with Down syndrome.
Reports show that an estimated 6 million people in the world have Down syndrome. In the United States, about 6,000 babies born every year have Down syndrome.
Moreover, approximately 45,000 Canadians and 15,000 Australians have the condition; and 104,000 European and 29,000 Indian babies are born with Down syndrome every year.
How many chromosomes do humans have?
Humans have 23 pairs of chromosomes, which makes a total of 46. However, a person with Down syndrome has a total of 47 chromosomes. Alternatively, a single chromosome may have an extra part.
Is Down syndrome genetic?
Down syndrome is a genetic disorder that involves producing an additional piece of genetic material known as chromosome 21. However, it’s essential to note that only 1% of all Down syndrome cases are hereditary, according to the National Down Syndrome Society. Also, heredity only applies in translocation, as trisomy 21 and mosaicism cannot be inherited.
Thanks to better medical care, therapy options, and increased awareness, there are fewer people with Down syndrome today than just a couple of decades ago. Additionally, while there is still no cure for the disorder, the Down syndrome statistics show that people with Down syndrome now live up to 60 years, compared to 25 in 1983.
As long as Down syndrome can be adequately managed, people with the disorder can live long and healthy lives and even have jobs.
Prenatal screenings and tests now exist to prepare expecting mothers for their babies. However, the availability of this screening has also led to high abortion rates in the past.
Nevertheless, the future remains bright for people with down syndrome, as researchers continue to develop more effective therapies and treatment.
- Canada Helps
- CBS News
- China Daily
- Down Syndrome Australia
- Down Syndrome Prenatal Testing
- European Union Science Hub
- Global Down Syndrome
- March of Dimes
- National Down Syndrome Society
- National Down Syndrome Society
- Pediatrics Nationwide
- Scielo South Africa
- The Henry Spink Foundation
- Toronto Sun
- Wiley Online Library