This article breaks down warning signs and symptoms of Down syndrome. We cover everything you need to know about screening and testing for Down syndrome, both during pregnancy and after birth.
You might recognize Down syndrome by its physical symptoms: round faces, small stature, and eyes that turn up at the corners. You might also be familiar with Down syndrome mental symptoms like learning difficulties, cognitive delays, and troubles with language.
But does everyone with Down syndrome share the same characteristics?
Short answer: No. Each person with Down syndrome is a unique and authentic individual, no matter their diagnosis.
In this article, Ability Central shares the most common symptoms of Down syndrome in infants, children, and adults. We also cover the diagnostic process for Down syndrome during pregnancy and for newborns.
- We answer questions like: What are the symptoms of Down syndrome?
- What are the physical symptoms of Down syndrome?
- What are the behavioral and cognitive symptoms of Down syndrome?
- What warning signs do doctors look for to test for Down syndrome during pregnancy?
- What screening tests identify Down syndrome risk during pregnancy?
- What diagnostic tests confirm Down syndrome during pregnancy?
- What tests verify Down syndrome after birth?
- Is Down syndrome inherited?
- Where can I get more information about Down syndrome?
What are the symptoms of Down syndrome?
Down syndrome is a genetic condition that affects development in multiple areas. Down syndrome symptoms can be:
- Physical
- Cognitive
- Behavioral
- A mix of all three
Every person with Down syndrome is a unique individual with their own symptoms, behaviors, and routines. To learn more about the types of Down syndrome and where they come from, see 9 Things You Should Know About Down Syndrome.
What are the physical symptoms of Down syndrome?
Some common physical features of Down syndrome include:
- A flattened face
- Almond-shaped or up-slanted eyes
- A shorter neck
- Smaller ears
- Larger tongues that might stick out of the mouth
- Small white spots on the iris, the part of the eye associated with eye color
- Smaller hands and feet, including small pinky fingers that often curve inward
- Loose joints or poor muscle tone
- Shorter height
- Palmar crease, a single line that stretches across the palm of someone’s hand
What are the behavioral and cognitive symptoms of Down syndrome?
Compared to their peers without the condition, babies and children with Down syndrome often experience:
- Developmental delays in walking, talking, and social skills
- Difficulty learning things like potty training, eating without help, or social cues
- Stubbornness
- Frequent tantrums
- Obsessive or compulsive behaviors, like strict adherence to routine, that become more obvious as the child grows older
As teenagers with Down syndrome, people might experience symptoms that continue into adulthood. These include:
- A significantly lower IQ
- A need for routine and sameness
- Unique communication needs, like relying on gestures and nonverbal communication rather than speech
- Self-talk, often as a way of processing information
- Difficulty with numbers (also called dyscalculia)
- Short-term memory problems, particularly verbal memory
- Behavioral changes, stubbornness, or tantrums, often set off by changes to someone’s routine or circumstances
- A higher risk of developing dementia or early-onset Alzheimer’s disease
What warning signs do doctors look for to test for Down syndrome during pregnancy?
Doctors often catch Down syndrome in screening and testing during pregnancy, but some families don’t find out if a baby has the condition until symptoms appear. Doctors use blood work, ultrasounds, and screening or diagnostic tests to estimate the risk of Down syndrome.
While the exact cause of Down syndrome is still unknown, one known link to Down syndrome is a pregnant woman’s age. The National Down Syndrome Society (NDSS) says the incidents of Down syndrome by age are as follows:
- At 20 years old, Down syndrome occurs in 1 in 2,000 births.
- At 25 years old, the rate increases to 1 in 1,200.
- At 30 years old, the rate is 1 in 900.
- At 35 years old, the rate is 1 in 350.
- At 40 years old, the rate is 1 in 100.
- At 45 years old, the rate is 1 in 30.
- By 49 years old, the rate is 1 in 10.
However, according to the American College of Obstetricians and Gynecologists, all pregnant women should take screening tests and diagnostic tests for Down syndrome, no matter their age.
What screening tests identify Down syndrome risk during pregnancy?
As mentioned in 9 Things You Should Know About Down Syndrome, Down syndrome testing can be broken into screening tests and diagnostic tests. In general, screening tests calculate the odds a baby might have Down syndrome, while diagnostic tests confirm or officially diagnose Down syndrome.
Screening tests may include blood tests or ultrasounds. These tests show the likelihood of the baby being born with Down syndrome, but they aren’t perfect. Blood tests and ultrasounds have very little risk to the mother or the baby, but they can’t predict Down syndrome with 100% accuracy.
For example, one Down syndrome warning sign doctors look for in ultrasounds is an EIF, or echogenic intracardiac focus. This is a bright spot on the baby’s heart visible during regular ultrasound checkups, and usually harmless.
Some doctors consider an EIF a “soft mark” for Down syndrome and recommend more testing if there is a positive result. However, an EIF is not always a sign of Down syndrome, and the test itself is sometimes inaccurate. That’s why doctors prefer modern screening and diagnostic tests designed specifically for Down syndrome.
The most common screening tests for Down syndrome are given in the first or second trimester.
The first trimester combined test is broken into two parts.
- First, a blood test measures the levels of certain proteins and hormones in the mother’s blood related to pregnancy. Abnormal levels of these substances may indicate a problem with the baby.
- Then, during a nuchal translucency test, an ultrasound measures the fluid at the back of the baby’s neck.
If you are the baby’s mother, your doctor, usually an obstetrician or geneticist, combines these two tests with your age to estimate your risk of having a baby with Down syndrome.
Another test called an integrated screening test monitors a pregnant woman’s bloodwork through the first and second trimesters. These tests look for certain proteins and other hormonal indicators of a higher Down syndrome risk.
What diagnostic tests confirm Down syndrome during pregnancy?
Diagnostic Down syndrome tests, usually performed if screening tests show high risk, are a bit more involved. Because these tests require more from the mother and the baby, they carry a low risk of miscarriage.
Diagnostic tests for Down syndrome include:
- Amniocentesis. Usually given in the second trimester, this test helps doctors take a closer look at chromosomes based on a fluid sample from the fetus’s neck.
- Chorionic villius sampling (CVS) can take place in the first semester. Doctors look at cells from the placenta to find potential chromosome changes.
- Preimplantation genetic diagnosis for parents using in vitro fertilization (IVF). Doctors check the egg for genetic changes before implantation.
For more information about these tests’ reliability and risks, see The 7 Most Important Things To Do After a Down Syndrome Diagnosis.
What tests verify Down syndrome after birth?
After birth, the baby’s appearance is often the first way doctors diagnose Down syndrome.
Physical features like the characteristic flat face, almond-shaped eyes, small hands and feet, and poor muscle tone help identify Down syndrome in infants.
Because babies withoutDown syndrome might have similar physical features, doctors use a chromosomal analysis called a karyotype to confirm the diagnosis.
Is Down syndrome inherited?
Couples who have had one child with Down syndrome have a slightly increased risk of having a second child with Down syndrome, but Down syndrome’s genetic links are still unclear.
Only 1% of all cases of Down syndrome have a hereditary component. According to the National Down Syndrome Society (NDSS), the risk of recurrence of translocation Down syndrome is about 3% if the father is the carrier and 10-15% if the mother is the carrier.
Where can I get more information about Down syndrome?
Ability Central offers a series of articles to further your knowledge about Down syndrome. See:
- 9 Things You Should Know About Down Syndrome
- The 7 Most Important Things To Do After a Down Syndrome Diagnosis
- Long-term Success and Support for People With Down Syndrome
