Diagnosing Down Syndrome -
The characteristics of babies born with
Down syndrome.

Information on diagnosing Down syndrome in pregnant woman and newborn babies.

diagnosing Down syndrome in babies.
Brian1.By Jennifer1982 (Own work)

Down syndrome babies are born with a chromosomal disorder.

Instead of the usual pair of chromosomes they have three copies of chromosome 21 ( trisomy 21).

This can happen when an error occurs during the cell division of the egg or the sperm cells (nondisjunction).

As a result the fertilized egg will end up with 47 chromosomes instead of 46. Down syndrome is the most frequently occurring chromosomal disorder with one in every 700 births.

Diagnosing Down syndrome when you are pregnant can be done through prenatal screening and diagnostic tests.


Diagnosing down syndrome through prenatal testing

Who needs prenatal testing (screening) for Down syndrome?

The American Congress of Obstetricians and Gynecologists recommends that all pregnant women, regardless of their age, should be offered screening for Down syndrome. Screening for down syndrome should be done in the first trimester.

  • Maternal blood testing-Abnormal levels of pregnancy-associated plasma protein-A( PAPP-A )and human chorionic gonadotropin (HCG)may indicate a higher risk of chromosome abnormalities like Down syndrome.
  • Nuchal translucency (NT) Screening- This test uses high resolution ultrasound to examine the size of a collection of fluid at the neck of the fetus. Prenatal screening tests can not determine with certainty if the baby has Down syndrome but will give you an estimate of having a baby with chromosomal abnormalities.

Diagnosing Down syndrome through diagnostic testing

Who needs diagnostic tests? If prenatal screening shows that your chance of having a baby with a chromosome disorder is higher than average, follow up testing is recommended. Most doctors use a chance of 1 in 270 as the treshhold for a high risk pregnancy.


A new maternal blood test for down syndrome!

Researchers have designed a new way of accurately diagnosing Down syndrome in pregnant women. This new method tests small amounts of fetal DNA in the mothers blood. At the moment the method needs further testing but they expect this non-invasive test to be introduced in the next few years. This new maternal blood test will save woman from current invasive methods like amniocentesis and cvs.


Diagnosing down syndrome by examining the chromosomes of the fetus can be done by:

1.Amniocentesis - a doctor extracts amniotic fluid (the liquid in the womb) to test the baby's chromosomes.

2.Chorionic Villus Sampling (CVS) - The doctor will take a sample of placenta tissue (chorionic villus) either through the woman's vagina or her abdomen. The placenta has the same genetic material as that in the baby's cells.

Prenatal screening and testing for Down’s syndrome is not compulsory. Whether a woman wishes to continue or terminate the pregnancy in case test results are positive is completely up to her and her partner.





When prenatal test results show your baby has down syndrome I recommend you read as much as you can about the subject. Take your time to find out what the condition means and learn what it is really like to live with a child who has down syndrome.

Some doctors may try to pressure you into making a decision because of the possible complications that come with a late abortion.


Gifts: Mothers Reflect on How Children with Down Syndrome Enrich Their Lives

This is an incredibly wonderful collection of personal stories, from families, about their feelings when they were given the diagnosis of Down syndrome.


Diagnosing Down syndrome after birth.

When a baby is born with down syndrome usually the doctor will notice the distinctive physical and facial features that come with this condition.

Typical Down syndrome characteristics are:

Face of a Down syndrome infant

Down syndrome characteristics
  • Upward slant to the eyes
  • Smaller ears, nose and mouth
  • Flat facial profile
  • Thicker than normal protruding tongue

Body of a Down syndrome infant

  • Poor muscle tone
  • Small hands and feet
  • Line in the palm of the hand
  • Gap between first and second toe

Diagnosing Down syndrome through Karyotype testing.

In some infants these down syndrome symptoms are more prominent than in others. When a doctor suspects down syndrome a special blood test will be done called chromosome analysis or karyotype testing. This test analyses the structure and the number of the baby's chromosomes.


karyo testing - chromosome analysis
Diagnosing Down syndrome.
Trisomy 21, chromosome 21 has an extra copy in babies with Down syndrome


Down syndrome prognosis

People with Down syndrome can live happy and productive lives and do normal things like other children. For example, join a sports team, attend a regular school or graduate from high school.

Medical conditions that often come with Down syndrome.

  • Congenital heart defects
  • Thyroid problems
  • Failure to thrive
  • Hearing and eye disorders
  • Obstructive sleep apnea
  • Leukemia
  • Seizures
  • Altzheimer later in life.

The life expectancy of children with Down syndrome has extended because of better medical care and children growing up with their families and not in institutions like they used to in the past. Early testing and treatment of common conditions that come with Down syndrome have improved their lives significantly.

People with Down syndrome usually do not live as long as other individuals mostly because of all these conditions. Over half of the children born with Down syndrome are expected to live into their fifties and 13,5% will still live when they reach 68.


Down syndrome prevention

Down syndrome is a genetic disorder and there is no way to prevent it yet. Even after years of intensive research we only know about certain risk factors of Down syndrome.

Measures you can take to reduce the chance of DS

  • Supplementation with folic acid before and during pregnancy is not only linked to neural tube defects but may also reduce the chance of Down syndrome.
  • Parents that already have a child with down syndrome are at an slightly increased risk of having a second child with this condition.
  • Down syndrome is closely related to maternal age. The older a woman gets the higher the risk of giving birth to a baby with Down's syndrome. Completing your family before the age of 30 would minimize your chance of Down syndrome.

Have a look at the following table to compare a mother's age with her chances of having a Down syndrome baby.

Mother's age Incidence of Down syndrome
20 1 in 2000
25 1 in 1200
30 1 in 900
35 1 in 350
40 1 in 100
45 1 in 30


Research shows that over 90% of pregnant woman diagnosed prenatally with Down’s syndrome decide to have an abortion. Some women refuse to have amniocentesis because regardless of the test results they want to keep the baby.

This can be for religious reasons or when a women beliefs abortion is unacceptable under any circumstances. Understandable woman that get pregnant after years of infertility treatment are often not prepared to take the small risk of miscarriage that comes with amniocentesis and CVS.

If you feel you are not able to care for a special needs child you could also consider putting your down syndrome baby up for adoption like this young mother did. There are waiting lists with people who are willing to adopt a child with Down syndrome.


Informative Down syndrome websites

National Down Syndrome Society envisions a world in which all people with Down syndrome have the opportunity to enhance their quality of life, realize their life aspirations, and become valued members of welcoming communities.

www.Cdadc.com is focused on the Diagnosis, Treatment and Cure of Down syndrome and of its symptoms.

Down syndrome education online focuses on the social development of individuals with Down syndrome.

Reece's Rainbow - The mission of Reece's Rainbow is to rescue orphans with Down syndrome through the gift of adoption, to raise awareness for all of the children who are waiting in 25 countries around the world.




To the top of Diagnosing Down Syndrome.