This means that Down syndrome occurs in about 1 in every babies. There are three types of Down syndrome. There are two basic types of tests available to detect Down syndrome during pregnancy: screening tests and diagnostic tests.
A screening test can tell a woman and her healthcare provider whether her pregnancy has a lower or higher chance of having Down syndrome. Screening tests do not provide an absolute diagnosis, but they are safer for the mother and the developing baby. Diagnostic tests can typically detect whether or not a baby will have Down syndrome, but they can be more risky for the mother and developing baby. Neither screening nor diagnostic tests can predict the full impact of Down syndrome on a baby; no one can predict this.
Extra fluid in this region could indicate a genetic problem. Rarely, screening tests can give an abnormal result even when there is nothing wrong with the baby. What is certain is that people with Down syndrome have the potential to learn throughout their lifetimes and that their potential can be maximized through early intervention , good education, high expectations, and encouragement from family, caregivers, and teachers.
Children with Down syndrome can and do learn, and are capable of developing skills throughout their lives. They simply reach goals at a different pace. People with Down syndrome often are regarded as particularly happy, sociable, and outgoing. While in general, this may be true, it's important to not stereotype them, even when it comes to labeling them with such positive characteristics. People who have Down syndrome experience a full range of emotions and have their own characteristics, strengths, weaknesses, and styles—just like anyone else.
There are some behaviors associated with Down syndrome that are largely due to the unique challenges the condition presents. For example, most people with Down syndrome tend to need order and routine when dealing with the complexities of daily life. They thrive on routine and will often insist on sameness. This can be interpreted as innate stubbornness, but that's rarely what's going on. Another behavior often seen in people with Down syndrome is self-talk—something everyone does sometimes. It's thought that people with Down syndrome frequently use self-talk as a way of processing information and thinking things through.
As you can see, it's hard to separate out some of the signs of Down syndrome from its potential complications. Keep in mind, though, that while many of the above issues pose undeniable concern, others simply chart a course for an individual that is out of "the norm. That said, people with Down syndrome are more likely than otherwise healthy people to have certain physical and mental health issues.
Care throughout one's life can be complicated by these additional concerns. According to the Centers for Disease Control and Prevention, up to 75 percent of children with Down syndrome will have some form of hearing loss. In many cases, this may be because of abnormalities in the bones of the inner ear. It's important to detect hearing problems as early as possible, since being unable to hear well can be a factor in speech and language delays. Children with Down syndrome are also at an increased risk of ear infections.
Chronic ear infections can contribute to hearing loss. As many as 60 percent of children with Down syndrome will have some type of vision problem, such as nearsightedness , farsightedness , crossed eyes , cataracts, or blocked tear ducts , according to the CDC. Half will need to wear glasses. The National Institutes of Health NIH states, "Down syndrome often causes problems in the immune system that can make it difficult for the body to fight off infections.
The condition is particularly common in Down syndrome because of physical anomalies such as low muscle tone in the mouth and upper airway, narrow air passages, enlarged tonsils and adenoids, and a relatively large tongue.
The American Academy of Orthopaedic Surgeons lists a number of issues affecting the muscles, bones, and joints of people with Down syndrome. One of the most common is an upper neck abnormality called atlantoaxial instability AAI , in which vertebrae in the neck become misaligned.
It doesn't always cause symptoms, but when it does it can lead to neurological symptoms such as clumsiness, difficulty walking or an abnormal gait e. About half of all babies with Down syndrome are born with heart defects, reports the CDC. These can range from mild problems that are likely to correct themselves over time to serious defects that will require medication or surgeries.
The most common heart defect seen in infants with Down syndrome is an atrioventricular septal defect AVSD —holes in the heart that interfere with the normal flow of blood. An AVSD may need to be surgically treated.
Children with Down syndrome who aren't born with heart problems will not develop them later in life. People with Down syndrome tend to be at an increased risk for a variety of GI problems. One of these, a condition called duodenal atresia , is a deformity of the small tube-like structure the duodenum that allows digested material from the stomach to pass into the small bowel. In a newborn, this condition causes a swollen upper abdomen, excessive vomiting, and lack of urination and bowel movements after the first few meconium stools.
Duodenal atresia can be successfully treated with surgery soon after birth. Another gastrointestinal condition of note in Down syndrome is Hirschsprung disease —an absence of nerves in the colon, which can cause constipation. However, younger women have more babies, so more children with Down syndrome are born to younger mothers. Reality : A recent Vanderbilt Kennedy Center study published in the American Association of Intellectual Disabilities indicates that divorce rates are lower in families of children with Down syndrome.
The study was one of the largest to date and included families who have children with Down syndrome. Reality : Studies do not support that a child with Down syndrome will have a negative impact on siblings. For example, a recent study published in the Journal of Intellectual Disability Research found no long-term detrimental effects to siblings. In fact, some mental health professionals point to the psychological advantages of such a child cared for within the family circle.
They have documented siblings who have increased tolerance, compassion and awareness, in contrast to all typical siblings. Reality : The average life expectancy for a person with Down syndrome is nearly 60 years old. Some people with Down syndrome have lived into their 80s. Unfortunately, the average life expectancy for an African-American in the U. This appalling statistic deserves the full attention of our government and scientific community.
Reality : An inability to walk is not a characteristic of Down syndrome. However, getting early physical therapy to ensure proper walking is important and builds the foundation for sports aptitude. Individuals with Down syndrome have a variety of athletic abilities and levels of agility, in the same way that typical people do. All over the world, there are sports teams that include people with Down syndrome including through Special Olympics. Still, many physicians are not fully informed about advising their patients about the incidences of Down syndrome, advancements in diagnosis, and the protocols for care and treatment of babies born with Down syndrome.
Heredity is not a factor in trisomy 21 nondisjunction and mosaicism. Most cases are sporadic — chance — events. However, in about one-third of cases, one parent is a carrier of a translocated chromosome. Once a woman has given birth to a baby with trisomy 21 nondisjunction or translocation, it is estimated that her chances of having another baby with trisomy 21 is 1 in up until age Genetic counseling can determine the origin of translocation.
There are two categories of tests for Down syndrome that can be performed before a baby is born: screening tests and diagnostic tests. Prenatal screens estimate the chance of the fetus having Down syndrome.
These tests do not tell you for sure whether your fetus has Down syndrome; they only provide a probability. There is an extensive menu of prenatal screening tests now available for pregnant women. Most screening tests involve a blood test and an ultrasound sonogram. The blood tests or serum screening tests measure quantities of various substances in the blood of the mother. New advanced prenatal screens are now able to detect chromosomal material from the fetus that is circulating in the maternal blood.
These tests are not invasive like the diagnostic tests below , but they provide a high accuracy rate. Still, all of these screens will not definitively diagnose Down syndrome. Prenatal screening and diagnostic tests are now routinely offered to women of all ages. The diagnostic procedures available for prenatal diagnosis of Down syndrome are chorionic villus sampling CVS and amniocentesis.
Amniocentesis is usually performed in the second trimester between 15 and 20 weeks of gestation, CVS in the first trimester between 9 and 14 weeks. Down syndrome is usually identified at birth by the presence of certain physical traits: low muscle tone, a single deep crease across the palm of the hand, a slightly flattened facial profile and an upward slant to the eyes.
Because these features may be present in babies without Down syndrome, a chromosomal analysis called a karyotype is done to confirm the diagnosis. They photograph the chromosomes and then group them by size, number, and shape. By examining the karyotype, doctors can diagnose Down syndrome. Another genetic test called FISH can apply similar principles and confirm a diagnosis in a shorter amount of time.
Individuals with Down syndrome are becoming increasingly integrated into society and community organizations, such as school, health care systems, work forces, and social and recreational activities.
0コメント