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Published: Sat, January 14, 2017
World | By Tasha Manning

Understanding the Diagnosis of Down Syndrome - National Down Syndrome Society

Understanding the Diagnosis of Down Syndrome - National Down Syndrome Society

Prenatal Testing & amp; Diagnosis

There are two types of tests for Down syndrome that can be performed before your baby is born: screening tests and diagnostic tests.

Prenatal Screenings

Prenatal Screenings 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. Diagnostic tests, on the other hand, can provide a definitive diagnosis with almost 100% accuracy.

There is an extensive menu of prenatal screening tests now available for pregnant women. Most of these 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, including alpha-fetoprotein, inhibin A, plasma protein A, estriol, and human chorionic gonadotropin. Together with a woman's age, these are used to estimate her chance of having a child with Down syndrome. Typically offered in the first and second trimesters, maternal serum screening tests are only able to predict about 80% of fetuses with Down syndrome. It is important to note that none of these prenatal screens will be able to definitively diagnose Down syndrome. Instead, mothers should expect results such as, "You have a 1 in 240 chance of having a child with Down syndrome" or "You have a 1 in 872 chance of having a child with Down syndrome."

These blood tests are often performed in conjunction with a detailed sonogram (ultrasound) to check for physical features that are associated with Down syndrome in the fetus. , Researchers have developed a maternal serum / ultrasound / age combination that can yield much higher accuracy at an earlier stage in the pregnancy. Even with the ultrasound, however, the screen will definitely not diagnose Down syndrome.

Maternal & Fetal Medicine - Monitoring High-Risk Pregnancies
Maternal & amp; Fetal Medicine is a subspecialty of the Obstetrics and Gynecology (OB / Gyn) Department at the Palo Alto Medical Foundation (PAMF).

Prenatal screening tests are now routinely offered to women of all ages. Diagnostic Procedures

The diagnostic procedures available for prenatal diagnosis are often used to diagnose prenatal diagnosis. Of Down syndrome are chorionic villus sampling (CVS) and amniocentesis. These procedures, which carry up to 1% risk of causing spontaneous termination (miscarriage), are nearly 100% accurate in diagnosing Down syndrome. Amniocentesis is usually performed in the second trimester between 15 and 22 weeks of gestation, CVS in the first trimester between 9 and 14 weeks. Amniocentesis and CVS are also able to distinguish between these genetic types of Down syndrome: trisomy 21, translocation Down syndrome, and mosaic Down syndrome.

Why Should I Get a Prenatal Test?

One of the best ways to begin to consider these choices is to speak to family members of individuals with Down syndrome through a local Down syndrome organization. In addition, there are many books and articles written by family members about their personal experiences. If you have any questions about these procedures, do not hesitate to contact us if you have any questions about these procedures. Do not hesitate to ask your doctor It is important that you receive accurate information and understand all your options.

Diagnosing Down Syndrome

Since many expectant parents choose to forgo prenatal tests, most cases of Down syndrome are diagnosed after the Baby is born Low muscle tone

Low muscle tone > A flat nose profile A small nose An upward slant to the eyes A single deep crease across the center of the palm Excessive space between large and second toe

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