Table of ContentsView AllTable of ContentsPrevalenceBy EthnicityBy Age and GenderCausesMortality RateScreening
Table of ContentsView All
View All
Table of Contents
Prevalence
By Ethnicity
By Age and Gender
Causes
Mortality Rate
Screening
People who are born with Down syndrome, also calledtrisomy21, have certainnoticeable traitsand health problems.
Theeffects of Down syndromeinclude:
All children who are born with Down syndrome develop one or more of these effects. However, many people who have Down syndrome usually do not develop all of the characteristics.
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Down Syndrome: Symptoms and Intellectual and Physical Traits
How Common Is Down Syndrome?
Down syndrome affects about one out of every 700 babies born in the United States, which is approximately 6,000 live births per year.More than 200,000 people in the United States are currently living with this condition.The incidence of Down syndrome has remained stable within the population.
No therapy can prevent the effects of the extra chromosome if a child has it. But the overall health of people with Down syndrome is improving due to early detection and treatment of serious health issues, like heart disease.
The self-care abilities of people with Down syndrome have improved over the years due to interventions like physical therapy and occupational therapy that can help people improve mobility and maintain independence.
For example, children who beginoccupational therapyat a young age or who receive learning interventions at school can achieve more independence than those who do not get these interventions.
One small research study found that children with Down syndrome are more likely to be overweight or have obesity if their parents are not counseled about the harmful health effects of obesity. In a small reasearch small study, Hispanic/Latino boys with Down syndrome were more likely to have obesity.
Down syndrome cannot develop later in life—a person not having an extra copy of chromosome 21 in utero cannot develop an extra copy later on. Additionally, Down syndrome is a lifelong condition that is not curable, and it does not go away on its own.
Because of the health effects and the risk of earlier-than-average age of death, Down syndrome is more common among children than adults, and the prevalence decreases with age.
Causes of Down Syndrome and Risk Factors
The extra chromosome can come from either parent. This occurs due to a biological error called nondisjunction that affects the egg or the sperm that fertilized the egg.
Some people havemosaic Down syndrome, in which some cells have three copies of chromosome 21 and some have two. In these cases, there is an error as the embryo’s cells are dividing in the very early stages of pregnancy.
While anyone of any age or background can have a child with Down syndrome, there are some risk factors. Risk factors include:
What Is Down Syndrome?
What Are the Mortality Rates for Down Syndrome?
There is a substantial variation in survival with Down syndrome, and severe heart and lung malformations are associated with lower survival.
Some babies born with severe organ defects might not survive beyond age 1, while children who have treatable defects or who do not have significant organ defects can survive for much longer.
The most common causes of death for people with Down syndrome are heart disease, lung disease, infections, dementia, and cancer.
Average LifespanThe average lifespan of a person with Down syndrome in the United States is approximately 55 years, which is compared to an overall average U.S. lifespan of 79.
Average Lifespan
The average lifespan of a person with Down syndrome in the United States is approximately 55 years, which is compared to an overall average U.S. lifespan of 79.
What to Know About Down Syndrome and COVID-19
Screening and Early Detection
The physical features of Down syndrome can be noticeable at birth, but sometimes parents, healthcare providers, and others might not notice that a child has Down syndrome until they are a few months old or older. Additionally, parents and others may be more likely to notice that a child looks like they have Down syndrome if there are risk factors.
Screening for Down syndrome includes testing during the pregnancy.
Prenatal Ultrasound
Quad Test
The quad testis a blood test that can be done after 15 weeks of pregnancy. It measures certain hormone levels that have been correlated with Down syndrome and other congenital conditions.This test does not provide a definitive diagnosis of Down syndrome.
Amniocentesis
Amniocentesistakes a sample of theamniotic fluid(the fluid surrounding the fetus) for chromosomal analysis. It is the most definitive diagnostic test for Down syndrome during pregnancy. It can be done after the 15th week of pregnancy. This procedure has a very low risk of complications.
RecommendationsScreening is recommended for pregnant people who are 35 years of age or older. It is also recommended for pregnant people younger than age 35 who have had a child with Down syndrome.Pregnant people who are at risk are not obligated to have screening for Down syndrome. Those who are at low risk can often request the screening tests.
Recommendations
Screening is recommended for pregnant people who are 35 years of age or older. It is also recommended for pregnant people younger than age 35 who have had a child with Down syndrome.Pregnant people who are at risk are not obligated to have screening for Down syndrome. Those who are at low risk can often request the screening tests.
Screening is recommended for pregnant people who are 35 years of age or older. It is also recommended for pregnant people younger than age 35 who have had a child with Down syndrome.
Pregnant people who are at risk are not obligated to have screening for Down syndrome. Those who are at low risk can often request the screening tests.
Summary
Down syndrome is a lifelong condition that occurs due to an extra copy of chromosome 21. This happens because of a genetic error that affects either the egg cell or the sperm cell that fertilized the egg to produce the child.
Down syndrome can cause many different physical problems, including abnormal musculoskeletal development, heart deformities, digestive problems, learning impairment, and more. It is a lifelong condition that can cause disabilities. Often, medical and practical interventions can alleviate some of the effects and improve quality of life.
Frequently Asked Questions
Most people who have Down syndrome do not have a family history of the condition. Down syndrome occurs due to a parental chromosomal abnormality, but it affects the child and not the parents. If a person with Down syndrome has a child, the child will have a 1 in 2 chance of inheriting Down syndrome.
Certain physical features and health problems occur as a result of having an extra copy of chromosome 21, but the effects can be slightly different for each person.For example, some people with Down syndrome can have serious heart malformations, while others may have mild heart involvement. The type of malformations each person has may differ.
Certain physical features and health problems occur as a result of having an extra copy of chromosome 21, but the effects can be slightly different for each person.
For example, some people with Down syndrome can have serious heart malformations, while others may have mild heart involvement. The type of malformations each person has may differ.
10 Sources
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