Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Down syndrome can also be diagnosed, or at least suspected, based on any of several prenatal tests including a nuchal translucency screening, sonogram, quadruple screen, or other blood tests.
Here is how Down syndrome is diagnosed in both scenarios. Modern imaging techniques can provide very detailed pictures of what's going on inside of the body, including features of a still-developing fetus. Since many characteristics of Down syndrome are visible, it's possible to pick up on some of them in an ultrasound before a baby is born.
While imaging tests can help indicate the possibility of Down syndrome, they cannot confirm it. Likewise, a negative test does not rule out Down syndrome. This specialized ultrasound, which is performed at 11 to 13 weeks, measures the thickness of an area of tissue at the back of a fetus's neck called the nuchal fold.
In general, a measurement under 3 millimeters mm is considered normal or screen negative and one that's over 3 mm is considered abnormal or screen positive. Ultrasounds work by using sound waves to generate an image of the fetus. These waves pose no risk to mother or baby.
The standard ultrasound is done between 18 and 22 weeks of pregnancy and can reveal a variety of physical characteristics that are associated with an increased risk that a developing baby has Down syndrome. The healthcare provider will rub a special gel on your abdomen and then slide a transducer, a wand-like apparatus that transmits sound waves into your abdomen, over your belly. The sound waves travel through the amniotic fluid, deflecting off of structures located in the uterus.
The speed at which the waves bounce back differs depending on the density of what they hit. A computer turns this information into an image of the fetus. The harder or denser a structure is, the brighter it will show up on the monitor. Occasionally, but not always, infants with Down syndrome show subtle signs, called soft markers, on an ultrasound that suggest they may have Down syndrome:. These signs do not mean that a baby has Down syndrome for sure.
Again, further testing is needed to confirm the diagnosis. Likewise, it is important to note that most fetuses with Down syndrome show no abnormalities on ultrasound, which can be falsely reassuring to parents who are especially concerned about this disorder.
It's important to know that blood tests are used for screening and, like imaging tests for the condition, only indicate the level of possibility that a child has Down syndrome. Negative screening results mean that your chance of having a baby with Down syndrome is low, but they do not guarantee there are no birth defects. If you have a negative result, you likely will not be offered follow-up diagnostic testing.
Positive screening results mean the chances a fetus has Down syndrome are higher than normal, and so follow-up diagnostic testing will be offered.
That said, most women with screen positive results will have normal healthy babies. This maternal blood test , which is part of routine prenatal care for all expectant moms, typically is performed between the 15th and 18th weeks of pregnancy. Two of these happen to be associated with Down syndrome:.
This relatively new test extracts DNA from both mother and fetus using a sample of the mother's blood and screens for chromosome problems such as Down syndrome as well as trisomy 13 and trisomy It can be done as early in pregnancy as 10 weeks but is not routinely done. According to the American College of Obstetricians and Gynecologists ACOG , healthcare providers will recommend cfDNA only for women with certain risk factors for fetal defects, including advanced maternal age 35 or over ; a fetal ultrasound that shows an increased risk of chromosome abnormality; a previous pregnancy with a trisomy; a positive first- or second-trimester maternal screening test; or a known balanced chromosome translocation in the mother or father.
It's important to understand that cfDNA testing can only indicate if a fetus is at an increased risk for a chromosome problem or is unlikely to have one. It is not a diagnostic test. It also is expensive, although the test may be covered by health insurance for women of advanced maternal age.
While these screenings can be helpful, the only way to definitively diagnose Down syndrome is to get a diagnostic test. If a prenatal screening test indicates there's a possibility your child will have Down syndrome or if you have risk factors for having a child with the disorder, then you may be faced with taking the next step and confirming the diagnosis.
This is an extremely personal decision, one that's fraught with dueling emotional and practical implications. It can be helpful to ask yourself very specific questions about whether prenatal testing to confirm a diagnosis of Down syndrome or any birth defect is the right thing for you and your family.
The ultrasound test is called measurement of nuchal translucency. In both tests samples are taken from the inside of your womb with a needle usually passed through your tummy.
Down syndrome can also be diagnosed after a baby is born. Clinicians can usually tell if a baby should be tested for Down syndrome based on a physical examination.
The first test, a rapid blood test FISH , confirms the presence of extra material from chromosome A triple screen looks for levels of three different markers; a quadruple screen looks for levels of four different markers. This approach uses both a blood test and an ultrasound during the first trimester as well as a second-trimester blood test. Health care providers then combine all these results to produce one Down syndrome risk rating. Amniocentesis pronounced am-nee-oh-sen-TEE-sis.
A health care provider takes a sample of amniotic pronounced am-nee-OT-ik fluid, which is then tested for the extra chromosome. This test cannot be done until week 14 to 18 of the pregnancy. A health care provider takes a sample of cells from a part of the placenta pronounced pluh-SEN-tuh , which is the organ that connects a woman and her fetus, and then tests the sample for the extra chromosome.
This test is done between weeks 9 and 11 of pregnancy. A health care provider takes a sample of fetal blood in the umbilical cord through the uterus. The blood is then tested for the extra chromosome. However, PUBS cannot be performed until later in the pregnancy, during the 18th to 22nd week. Chromosomal Testing of Maternal Blood A pregnant woman who is at risk for having an infant with Down syndrome also can have a chromosomal test using her blood.
Testing and In Vitro Fertilization Another approach to diagnosis is used in conjunction with in vitro fertilization. ACOG's screening guidelines on chromosomal abnormalities [News release].
Retrieved June 11, Driscoll, D. Clinicians can usually tell if a baby should be tested for Down syndrome based on a physical examination. The first test, a rapid blood test FISH , confirms the presence of extra material from chromosome Results are available within a few days. A karyotype test is a blood test that takes about one to two weeks for results. This provides further information on the type of Down syndrome, which is important in determining the chance of trisomy 21 in a future pregnancy.
While there is no cure for Down syndrome, there are a variety of treatments and therapies to address a child's unique medical issues and developmental profile. Almost half of children with Down syndrome are born with congenital heart defects. Babies with congenital heart conditions are treated by pediatric cardiologists, doctors who specialize in diagnosing and treating heart problems.
Treatment is based on the severity of the child's heart condition. Some mild heart defects don't require any treatment. Others can be treated with medications, interventional procedures, or surgery. Surgery may be necessary to treat upper neck abnormalities and stomach problems. Most of the educational therapies used to address the core symptoms of Down syndrome are provided through programs run by states and local school systems.
Most children with Down syndrome can spend at least some of their time in a general education classroom with typically developing peers but some children can benefit from a smaller setting with more individual support.
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