Author: Charles Marsan

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Prenatal testing for Down syndrome

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In this section, we first explain what prenatal testing is. Then, we explain the reasons prenatal testing is offered, and why people do it or not. Finally, we describe the various types of prenatal testing.

What is prenatal testing for Down syndrome?

What are the reasons to have prenatal testing for Down syndrome?

    • Why is it offered and is it mandatory?
    • Why do people do it or not?

How is prenatal testing for Down syndrome done?

    • Prenatal screening
      • Nuchal translucency (NT) scan
      • Serum screening
      • Non-invasive prenatal screening (NIPT)
    • Prenatal diagnosis
      • Amniocentesis
      • Chorionic villus sampling (CVS)

References

What is prenatal testing for Down syndrome?

Here are the terms you need to know when you make decisions about prenatal testing.

TermDefinition
PrenatalPrenatal means “before birth”. All the tests that are discussed on this page are done in the first half of pregnancy.
Down syndromePeople with Down syndrome have delayed intellectual and physical development. Most children with Down syndrome learn to walk and talk. They also learn to take care of their basic needs. However, it usually takes them longer to get there. Many children with Down syndrome attend regular schools. People with Down syndrome live until about 60 years old. They can have health issues such as heart defects. Most people and families living with Down syndrome report being happy. Adults with Down syndrome can live alone, with their parents, in group homes or in residences.  Most need some type of supervision.

For more information,

check out the “Down syndrome” section.

Prenatal screening for Down syndromeA test that tells you if your baby as a high chance or a low chance of having Down syndrome. There is no risk of losing the baby with prenatal screening. It requires a blood test and/or an ultrasound.
Prenatal diagnosis for Down syndromeA test that tells you if your baby has Down syndrome or not. There is a very small risk of miscarriage with prenatal diagnosis. It requires collecting samples from inside the womb with a needle.
Prenatal testing for Down syndromePrenatal screening and diagnosis for Down syndrome. 
Positive prenatal screen for Down syndromeWhen prenatal screening says that your baby has a high chance of having Down syndrome.
Negative prenatal screen for Down syndromeWhen prenatal screening says that your baby has a low chance of having Down syndrome.
Positive prenatal diagnosis for Down syndromeWhen prenatal diagnosis says that your baby has Down syndrome.
Negative prenatal diagnosis for Down syndromeWhen prenatal diagnosis says that your baby does not have Down syndrome.

What are the reasons to have prenatal testing for Down syndrome?

Why is it offered and is it mandatory?

There are common beliefs about reasons for prenatal testing. Here is a list of beliefs and realities about prenatal testing.

BeliefReality
Prenatal testing is mandatoryPrenatal testing is offered to all pregnant patients but it is not mandatory.
Prenatal testing is recommended by doctors.Doctors offer prenatal testing to all pregnant patients. It is a personal choice whether to do it or not.
Prenatal testing is part of the “routine” pregnancy follow-up.Prenatal testing is “routinely” offered. However, it is a personal choice whether to do it or not.
The government pays for prenatal testing. This means that it is better to do it than not.The government pays for prenatal testing to ensure equal access for those who want to do it. It does not mean that it is better to do it than not.
Prenatal testing aims to get rid of Down syndrome by aborting all the babies with Down syndrome.The goal of prenatal testing is to offer information to pregnant patients. Based on this information, some pregnant patients do choose to end the pregnancy. Others use the information to prepare in advance for raising a child with special needs. Some couples plan for adoption.
Prenatal testing for Down syndrome is the most common kind of prenatal testing because Down syndrome is the worst condition a baby could have.Testing for Down syndrome is more common and has been done for longer. This is because Down syndrome is easy to identify in the lab. It is not because it is worse than other conditions a baby could have.
I should do everything that I can to avoid having a baby with Down syndrome.This is a personal choice. There is no right or wrong answer. There is no “should”. People with Down syndrome and their family are usually happy.
My chances of having a baby with Down syndrome are higher because I am over 35 years old. This means that I should do prenatal testing.It is true that the chances of having a baby with Down syndrome increase with age. Yet, babies with Down syndrome are born to mothers of all ages. No matter how old you are, it is always a personal choice to do prenatal testing or not. 
I will have to do prenatal diagnosis if I get a positive prenatal screen.A positive prenatal screen does not mean that you have to do prenatal diagnosis. It is a personal choice.

After a positive prenatal screen you may:

–       choose to stop testing and continue the pregnancy.
–       choose to do prenatal diagnosis to confirm the results.

For people with a positive prenatal screen who wish to terminate the pregnancy if the fetus has Down syndrome, confirming the results with prenatal diagnosis is strongly advised.

I will have to terminate my pregnancy if I get a positive prenatal diagnosis.A positive prenatal diagnosis does not mean that you have to terminate the pregnancy. It is a personal choice.
Prenatal testing is a good way for me to feel reassured that my baby does not have intellectual disability.Down syndrome accounts for 6 to 8 in 100 cases of intellectual disability. In other words, most cases (92 to 94 in 100) of intellectual disability have other causes. Therefore, negative prenatal testing does not mean that a baby will be “typical”. For instance, there is no prenatal testing for autism. 

Why do people do it or not?

There are many reasons for people to choose to do prenatal testing. There are also many reasons for people to choose not to do it. There is no right or wrong choice.

Reasons for doing prenatal screeningReasons for declining prenatal screening
If my baby has Down syndrome, I will make changes to my birth plans.

If my baby has Down syndrome, I prefer to prepare in advance. 

If my baby has Down syndrome, I prefer to arrange for an adoption.

If my baby has Down syndrome, I prefer to terminate the pregnancy.

I am not decided about the above. I prefer to think about this only if my baby has Down syndrome. 		I would not change my birth plans because of Down syndrome.

I do not feel the need to prepare in advance for a baby with Down syndrome.

I would not choose adoption because of Down syndrome.

I would not choose to terminate my pregnancy because of Down syndrome.

I do not want to be stressed about the results.

I want a less medicalized pregnancy.

I am opposed to prenatal screening for philosophical or religious reasons.
Reasons for doing prenatal diagnosis after a positive prenatal screenReasons for declining prenatal diagnosis after a positive prenatal screen
I want to know for sure if my baby has Down syndrome. I do not want to worry for the rest of my pregnancy whether my baby might have Down syndrome.

I will end my pregnancy if my baby has Down syndrome.		I do not want to risk losing my baby.

I do not want an invasive test.

I do not want to terminate my pregnancy.

Learn more

It is important to understand why prenatal testing is offered specifically for Down syndrome (Trisomy 21). This emphasis on Down syndrome is not because it is the worst condition a child can have. It is also not because people living with Down syndrome do not have a good quality of life or a ‘life worth living’. In fact, many people who have first-hand experience with Down syndrome do not consider it to be something that needs to be avoided.

      • The first reason testing for Down syndrome is offered is that it is possible. The genetic basis of Down syndrome (3 rather than 2 chromosomes 21) is easy to identify and it is well researched and understood. This is not the case with most other causes of intellectual disability or other congenital anomalies. There are other conditions that are easy to diagnose during pregnancy, such as neural tube defects, Edwards syndrome, or trisomy 18, and Patau syndrome, or trisomy 13. These conditions are often screened for at the same time as Down syndrome.
      • The second reason for the emphasis on Down syndrome is that of all the known causes of intellectual disability, it is the most common. Yet, if we consider all the other causes taken together (combined), then they are responsible for 92-94% of the cases of intellectual disability. In other words, Down syndrome is responsible for about 6-8% of intellectual disability cases. This means that terminating a pregnancy on the basis of Down syndrome does not eliminate the probability of having a child with an intellectual disability.

The purpose of prenatal testing is to identify the presence of Down syndrome in the fetus. Parents may choose to use this information for various reasons:

      • They may want to have this information because it involves an increased risk of complications during delivery. They may want to change their plans for the birth (for example, have the baby at the hospital rather than at home).
      • They may want to have this information to prepare in advance for the birth of a child with Down syndrome (for example, read about Down syndrome, find out about available services, and connect with support groups).
      • They may want to have this information because they prefer not to have a child with Down syndrome and would choose to terminate the pregnancy if the fetus is diagnosed with it.
      • They may want to have this information because they would continue the pregnancy but would like to make plans for the child to be adopted.

To learn more about the possible pregnancy decisions after a positive diagnosis, click here.

Whatever the reason, pregnant patients should always be offered prenatal testing. They should never be pressured or guilted into doing or not doing it.

Choosing to use prenatal testing or not to use it, is a personal decision. Pregnant patients may want to make this decision alone, or with their partner. They may wish to discuss it with friends, family members and/or health care providers. The role of health care providers in prenatal testing is to provide all the information and counseling necessary for the pregnant patient/couple to make their decision.

The fact that prenatal testing is routinely offered and the fact that some tests are paid for by the Canadian public healthcare system (or by the government or insurance in other countries) does not mean that it is better to use them than not to use them. Prenatal tests are tools that are made available to pregnant patients to help them make choices that suit their needs and preferences. Choosing not to use these tools is as valid as choosing to use some of them or all of them.

How is prenatal testing for Down syndrome done?

Prenatal screening

Prenatal screening is a test that tells you if you baby as a high chance or a low chance of having Down syndrome. There is no risk of losing the baby with prenatal screening. It requires a blood test and/or an ultrasound. There are three types of prenatal screening: Nuchal translucency scan, serum screening, and non-invasive prenatal screening (NIPT).

Learn more about probabilities (chance)

Prenatal screening methods used together or separately, give a chance of the fetus having Down syndrome. This chance is described as ‘high’ or ‘low’. The cut-off between ‘high’ and ‘low’ varies between programs but it is generally around 1/300.

To understand probabilities better, it can be useful to present them in various forms.

For example:

      • A 1/300 probability that the fetus has Down syndrome means that in a group of 300 pregnant patients, one will have a fetus with Down syndrome.
      • A 1/300 probability that the fetus has Down syndrome also means a 299/300 probability that it does not have Down syndrome. Therefore, it means that that in a group of 300 pregnant patients, 299 will not have a fetus with Down syndrome.
      • A 1/300 probability that the fetus has Down syndrome means a 0,3% probability that it has Down syndrome and a 99,7% probability that it does not.

The cut-off points for probabilities to be considered ‘high’ or ‘low’ are set with the intention of maximizing detection rates while minimizing false-positive rates. The detection rate is the proportion of babies with Down syndrome that are given a “high-chance” result. The false-positive rate is the proportion if babies without Down syndrome that are given a “high-chance” result.

It is useful to understand this because many people experience anxiety when they hear that they have a “high chance” after screening. Calling the result “high chance/risk/probability” can be misleading. Most people would consider that if an event has a 1 in 250 or 1 in 300, or even a 1 in 100 chance of occurring, it is not “highly likely” that this event will occur. Indeed, a large majority of those who get a “high chance” result after nuchal translucency scan or serum screening do not carry a baby with Down syndrome. Less than 5% of fetuses with a positive serum screen actually have Down syndrome. This is called the “positive predictive value” (PPV).

A 5% positive predictive value means that a pregnant patient who has received a “high chance” result that the fetus has Down Syndrome has a 5% chance that the fetus does have Down Syndrome and 95% chances that the fetus does not have Down Syndrome.

Interpreting a risk/chance level is very subjective and personal. Different people may have very different understandings and feelings about what is an acceptable risk for them.

Individual patients may decide for themselves what they consider to be high chance/risk/probability. Based on this, they may pursue follow-up options (diagnostic testing) or not, depending on their own tolerance of risk. However, public prenatal testing programs do set eligibility criteria. Consider the following examples.

      • Mary’s fetus has been identified as having a 1 in 30 chance of having Down syndrome. Mary finds this probability quite high. The public health system in her province has a cut-off point at 1 in 300. Mary will be eligible for further testing in the public system and will pursue it. Depending on the province she lives in, she may have free access to NIPT before she is offered diagnostic testing (amniocentesis).
      • Lucy’s fetus has been identified as having a 1 in 350 chance of having Down syndrome. Lucy finds this probability quite high. The public healthcare system in her province has a cut-off point at 1 in 300. Lucy will not be eligible for further testing in the public system, but she will pursue further testing privately and pay for it out-of-pocket.
      • Chloe’s fetus has been identified as having a 1 in 250 probability of having Down syndrome. Chloe finds this probability quite low. The public healthcare system in her province has a cut-off point at 1 in 300. Chloe would be eligible for further testing in the public system, but she chooses not to do any more tests.

It is also important to consider that the type of results provided by screening never completely eliminates the probability of the fetus having Down syndrome. For instance, when the screening result is 1 in 25 000, it still means that out of 25 000 pregnant patients with this result, 1 is indeed carrying a fetus with Down syndrome.

A diagnostic test is required if a person wishes to completely eliminate the uncertainty regarding Down syndrome. In this case, the probability of the fetus having Down syndrome needs to be weighed against the risk of a miscarriage occurring because of the diagnostic test. Statistically, this risk of such a miscarriage is estimated between 1 in 200 (0.5%) and 1 in 500 (0.2%). In addition to the probability of each event, people may consider which event they wish to avoid the most – a miscarriage or the birth of a child with Down syndrome. There is no right or wrong answer to this question. It is very personal.

Nuchal translucency scan (NT scan)

The NT scan is an ultrasound that looks at the neck of the baby. It measures a layer of fluid that all babies have at the back of their neck. When the there is more fluid, there is a higher chance that the baby might have Down syndrome.

The NT scan is done between week 11 and week 13 of pregnancy. It is often done with serum screening. Out of 100 babies with Down syndrome, this type of prenatal screening will find about 85. 

If your NT is positive, your doctor will offer you NIPT and/or prenatal diagnosis.

The NT scan can also detect signs of trisomy 18 and trisomy 13 and heart defects. 

Learn more on NT scans

Other body features of the fetus also provide useful information at this point. For instance, the absence of a nose bone is also an indicator for a higher probability of trisomies. In addition, some organs can be visualized, the heartbeat can be heard, and the fetus can be measured to monitor fetal development.

Serum screening

Serum screening is a blood test that detects signs that the baby has Down syndrome.  This test measures hormone and protein levels from the baby and placenta. 

Some programs use a single blood draw in the first trimester. Others also use a second blood draw in the second trimester. The first sample is taken at week 10 to 13. The second sample is ideally taken 3-4 weeks later, at week 14 to 16. It can be done until week 20.

Serum screening also detects signs of Trisomy 13 (Patau syndrome), Trisomy 18 (Edward syndrome) and neural tube defects.

Serum screening is often done with the NT scan. Out of 100 babies with Down syndrome, this type of prenatal screening will find about 85.

If your serum screening is positive, your doctor will offer you to take NIPT and/or prenatal diagnosis

Learn more about serum screening

Different screening programs and different physicians offer various combinations of the first and/or second trimester serum screening with NT scan and/or NIPT. Using the second trimester serum screening has the advantage of making the results more accurate, and the disadvantage of delaying the results of screening.

A few examples:

A combination called “Enhanced First Trimester Prenatal Screening” uses the first trimester serum screening and the NT scan. It gives a result in the first trimester with an 83% detection rate and 5% false-positive rate. If a pregnant patient ‘screens positive’, it means that she is given a ‘high chance’ result based on this screening combination. In this case, the patient may access NIPT or prenatal diagnosis in the first trimester or early in the second trimester. This screening combination is offered by the Ontario and Saskatchewan public programs, as well as in private clinics across Canada.

Another combination called “Serum Integrated Prenatal Screening” uses the serum screening from the first and second trimesters. It gives a probability result in the second trimester with an 85% detection rate and a 4% false-positive rate. If a pregnant patient ‘screens positive’, it means that she is given a ‘high chance’ result based on this combination. In this case, the patient may access NIPT or diagnostic tests later in the second trimester. The Serum Integrated Screen is offered by the Quebec and British Columbia public program and by private clinics across Canada.

A third combination called “Integrated Prenatal Screening” uses the serum screening from the first and second trimesters with the NT scan. It gives a probability result in the second trimester with an 87% detection rate and a 2% false-positive rate. If a pregnant patient ‘screens positive’, it means that she is given a ‘high chance’ result based on this combination. In this case, the patient access NIPT or diagnostic tests later in the second trimester. The Integrated Screen is offered by the Quebec and British Columbia public program, in locations where nuchal translucency is available, and by private clinics across Canada.

NIPT

NIPT stands for “non-invasive prenatal testing” and it tests cfDNA which means “cell-free DNA”. Pregnant patients have little bits of DNA from the placenta in their blood. This DNA is a lot like the baby’s DNA. NIPT test looks at this cfDNA to identify fetus with a high chance of having Down syndrome. 

You may know NIPT under a different name:

    • NIPS (Non-Invasive Prenatal Screening)
    • cfDNA screening 
    • Commercial names : Panorama, Harmony, Verify, and others. (None of the commercial NIPT companies currently meet all the basic recommendations of the American College of Medical Genetics and Genomics. Click here for more information.)  

NIPT can be done as of week 9. However, it is most often done after a positive NT scan or serum screening. Out of 100 babies with Down syndrome, this type of screening will identify about 99. 

NIPT is more accurate than NT scans and serum screening for detection of Down syndrome. However, it is more expensive. It is not paid for by all provinces, nor by all private insurances.

Although NIPT is very accurate, both false positive and false negative results can occur. Therefore, those who wish to end a pregnancy after a positive NIPT need to confirm the result with prenatal diagnosis.

Learn more on NIPT

In addition to Down syndrome, NIPT can also test for other conditions where the fetus has an extra chromosome, including Patau syndrome and Edwards syndrome. It can also test for conditions caused by a nontypical (extra or missing) numbers of sex chromosomes: Klinefelter syndrome, Turner syndrome and triple X syndrome.

Typically, females have two X chromosomes (XX) and males have one X chromosome and one Y chromosome (XY). Any other number of sex chromosomes will lead to syndromes in the fetus that vary from mild to life-threatening. People who receive a “positive screen” for one of these less-common syndromes will be offered follow-up prenatal diagnosis and medical information specific to that condition. NIPT cannot find neural tube defects (NTDs) that can be found by serum screening. Most neural tube defects are identified by ultrasound in the second trimester.

Although NIPT can be performed as early as week 9 or 10, many professional associations recommend using it only in pregnancies with high probability of having a condition. A pregnancy is considered “high probability” (sometimes referred to as “high risk”) when:

      • Another screening test, such as screening serum and/or a nuchal scan gave a “high-probability” result.

Or

      • The pregnant woman will be 40 years old or more at the expected time of delivery.

Or

      • There is a personal or family history of a condition that can be found by NIPT.

Some Canadian provinces currently do not cover the cost of NIPT through public healthcare. Ontario, Manitoba, British Columbia, Quebec, Nova Scotia and Newfoundland and Labrador have added NIPT to their prenatal screening programs for high probability pregnancies. NIPT is available in private clinics across Canada for high probability and low probability pregnancies. It may also be available as part of clinical trials in some locations.

NIPT gives results that are more reliable than nuchal scans and serum screening. In high probability pregnancies, NIPT detects 99 out of 100 fetuses that have trisomy 21, 18 or 13.

However, NIPT is not as certain as a diagnostic test. This means that it can give a “positive result” even if the baby does not have the condition. This is called a “false-positive”. False-positives happen frequently, especially in low probability pregnancies. Because of this, a diagnostic test (CVS or amniocentesis) is recommended for:

      1. People who want to be as sure as possible about the result.
      2. People considering terminating the pregnancy after a positive NIPT.

However, false-negatives (a negative screen when the fetus actually has a trisomy) are rare with NIPT.

In about 1% to 8% of cases the test does not give a result. In these cases, the chance of a chromosomal trisomy, especially trisomy 13 (Patau syndrome) and trisomy 18 (Edwards syndrome) is increased and the NIPT should be repeated or other tests can be used.

Prenatal diagnosis

Prenatal diagnosis is a test that tells you if your baby has Down syndrome or not. It can also tell you if your baby has other chromosomal abnormalities not detected by screening, such as rare trisomies and chromosomal rearrangements. There is a small risk of losing the baby with prenatal diagnosis. It requires collecting samples from inside the womb with a needle. The two types of prenatal diagnosis are amniocentesis and chorionic villus sampling (CVS).

If you have a positive screen, you will be offered prenatal diagnosis. However, this does not mean that you have to do it. Doing prenatal diagnosis or not is a personal choice. Some people want to know as much as possible. Some people prefer not to know in advance. For some people, the information is worth the risk. For others, it is not.

Amniocentesis

To do amniocentesis, the doctor collects liquid from inside the womb with a needle. The needle goes through the belly. The liquid is called “amniotic fluid”. It contains DNA from the baby. It can be done from week 15 of the pregnancy. There is a small risk of pregnancy loss (miscarriage) after amniocentesis. The risk is between 0.2% and 0.5% (1 in 500 to 1 in 200). It can happen whether or not the fetus has Down syndrome.

Learn more on amniocentesis

Amniocentesis is the most common type of prenatal diagnostic test. It involves collecting a small sample of amniotic fluid from the uterus, using a fine needle that is inserted through the pregnant patient’s abdomen, under ultrasound guidance. This fluid contains fetal cells from which chromosomes, or DNA, can later be analyzed. Amniocentesis can be done from week 15 of the pregnancy.

Advantages:
Amniocentesis provides a diagnosis (definite result), as opposed to a probability, or a likelihood/chance. It is more widely available than CVS and it fails in less cases than CVS.

Disadvantages:
Discomfort can be felt from the needle insertion. Amniocentesis involves an increased risk of miscarriage estimated at 0.2-0.5% (1 in 500 to 1 in 200). Other possible complications include pain, cramps, bleeding, fever, and loss of amniotic fluid.

Compared to CVS, the test is done later in the pregnancy, and analyzing the sample may take longer (2 to 4 weeks), although results can be obtained faster (4-6 days). This leaves less time for decision-making. If someone chooses to terminate the pregnancy because of the results of amniocentesis, the termination would occur later in the pregnancy.
After the amniocentesis, it is recommended to rest for 24 hours.

Chorionic villus sampling (CVS)

To do CVS, the doctor collects cells from the placenta, called villi, with a catheter. They contain DNA from the baby. The catheter goes through the belly or inside the vagina. CVS can be done between 11 and 14 weeks of pregnancy. There is a small risk of pregnancy loss after CVS. The risk is 0.5% to 1%. In 200 CVS, 1 or 2 pregnant patients lose their baby. It can happen whether or not the fetus has Down syndrome.

Learn more about CVS

Chorionic villi are little branches in placental tissue that reach out in the wall of the mother’s womb to help the flow of blood between the mother and fetus. Therefore, villi are the placental structures that are most easily accessible from the outside. CVS consists of collecting a small piece of villi with a needle or catheter. The procedure is guided by ultrasound and may be done through the abdomen or vagina. The actual procedure takes less than one minute but it takes overall approximately 10-20 minutes including the preparation. It is performed between weeks 11 and 14 of pregnancy.

Advantages:
CVS provides definitive results, as opposed to a probability or a likelihood/chance, early in the pregnancy, which leaves more time for decision-making about the pregnancy. Results are usually provided within 2 weeks.

Disadvantages:
There is an increased risk of miscarriage estimated at 0.5-1% (1 in 200 to 1 in 100). Discomfort or pain can be felt from the needle insertion. Other possible complications include pain, cramps, bleeding, fever, and loss of amniotic fluid. Test failure: in 1 to 2% of cases, the results may be inconclusive due to the presence of maternal tissue in the collected sample or other technical problems. In these cases, either a new CVS or an amniocentesis could be offered.

After the procedure, it is recommended to rest for 24 hours.

References

See references
ACOG (2015). “Cell-free DNA screening for fetal aneuploidy.” American College of Obstetricians and Gynecologists. Journal of Obstetrics and Gynaecology Canada 2015 Vol. 37 Issue 7 Pages 656-668.

ACOG (2016). “Screening for Fetal Aneuploidy.” American College of Obstetricians and Gynecologists. Obstetrics & Gynecology 127(5). e123-e137.

Cartier, L., L. Murphy-Kaulbeck, R. D. Wilson, F. Audibert, J.-A. Brock, J. Carroll, L. Cartier, A. Gagnon, J.-A. Johnson, S. Langlois, L. Murphy-Kaulbeck, N. Okun and M. Pastuck (2012). “Counselling Considerations for Prenatal Genetic Screening – SOGC Committee opinion.” Journal of Obstetrics and Gynaecology Canada 34(5): 489-493

Marteau, T. M., J. Kidd, R. Cook, S. Michie, M. Johnston, J. Slack and R. W. Shaw (1991). “Perceived risk not actual risk predicts uptake of amniocentesis.” Br J Obstet Gynaecol 98(3): 282-286.
MSSS (2010). “Programme québécois de dépistage prénatal de la trisomie 21 — Cadre de référence.” Ministère de la Santé et des Services sociaux. Gouvernement du Québec. http://publications.msss.gouv.qc.ca/msss/document-000783/.

MSSS (2020). Programme québécois de dépistage prénatal de la trisomie 21. Gouvernement du Québec, Ministère de la Santé et des Services sociaux du Québec,. 20-931-014F. https://publications.msss.gouv.qc.ca/msss/fichiers/2020/20-931-04F.pdf

MSSS (2023). Programme québécois de dépistage prénatal. Élargissement de l’offre. Guide informationnel destiné aux professionnels de la santé. Document provisoire. https://www.msss.gouv.qc.ca/professionnels/documents/pqdp/Formation_professionnels_COVID19_2023-04-05.pdf

Prenatal Screening Ontario. (2021). “Prenatal Screening Ontario.” Government of Ontario http://prenatalscreeningontario.ca/.

Slovic, P. (1987). “Perception of risk.” Science 236(4799): 280-285.

Wilson, K. L., J. L. Czerwinski, J. M. Hoskovec, S. J. Noblin, C. M. Sullivan, A. Harbison, M. W. Campion, K. Devary, P. Devers and C. N. Singletary (2013). “NSGC Practice Guideline: Prenatal Screening and Diagnostic Testing Options for Chromosome Aneuploidy.” Journal of Genetic Counseling 22(1): 4-15.

Wilson, R.D., et al., Prenatal Diagnosis Procedures and Techniques to Obtain a Diagnostic Fetal Specimen or Tissue: Maternal and Fetal Risks and Benefits – SOGC Clinical practice guideline. Journal of Obstetrics and Gynaecology Canada, 2015. 37(7): p. 656-668.

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Food for Thought

Version française

Some people hold strong views about prenatal testing. Some of them oppose it. Others find it very important. These views can feed into your thinking, so we present them here. However, it is important to remember that what matters is that you get to make your own decision.

We discuss the following topics:

Reproductive autonomy (free choice in reproduction)

Some people hold strong views about the pros and cons of prenatal testing. Some oppose it. Others believe it is essential. Reading about these views can inform your thinking. However, most people agree that what matters most is that people (prospective parents) have the ability to make their own choices.

Autonomy is the ability to make choices for yourself. Choices should be free and informed. Free choice means that nobody puts pressure on you to choose a certain option. Informed choice means that you have all the information you need to make your choice. You can make choices based on your values and preferences.

Reproductive autonomy is the ability to make choices about having children. People should be allowed to choose if they want to have children or not. They should also be allowed to choose when to have children. Prenatal testing allows parents to know in advance if their child will have a disability or a medical condition. Prenatal testing is offered to all parents. It is a personal decision to use it or not.

Choosing not to use prenatal testing can be a free and informed choice. Choosing to use it can be a free and informed choice as well. To make this choice, you may want to learn more about different topics:

      • The pros and cons of prenatal testing in general
      • The pros and cons of the specific test that is offered
      • The condition that is being tested (for example, Down syndrome)
      • The experience of families living with this condition

After a positive diagnosis based on prenatal testing, you may wish to consider whether to continue or end your pregnancy. This decision should also be free and informed. You may want to learn about different topics to make your choice:

      • The condition that was diagnosed
      • The experience of families living with this condition
      • The resources available in your area for people with this condition and their families
      • The pros and cons of abortion

Doctors and midwives give you information to help you make these decisions. They should not put pressure on you to choose one option over another.

Resources like this website and local advocacy groups can be helpful to find more information.

The experience of pregnancy

Some people find that prenatal testing changes how they experience their pregnancy. Some wait for test results to tell family and friends that they are pregnant. Others wait for test results to “bond” with the baby.  This changes how women experience their first pregnancy signs. It can change the support they receive. Waiting for the results can be stressful. Testing requires decisions that some people prefer not to make. Some people prefer a simple pregnancy experience with less medical intervention.

Disability rights

Some people reject the view that disability leads to a worse life. For them, we should not choose children who have better chances to be typical. Instead, we should make the world more inclusive and respectful of diversity.  

Many of these people think that prenatal testing discriminates against people with the tested conditions or that it harms them. For example, wanting to avoid Down syndrome sends a hurtful message to people with Down syndrome. It would be like saying “I don’t want my children to be like you”, or even “I think the world is better without people who have Down syndrome”.

Learn more

The ‘disability rights’ critique of prenatal testing

Many disability rights activists and disability scholars (researchers who study disability) criticize prenatal testing. They view the issues raised by disability, such as limited opportunities and barriers to access, as caused by our social and physical environment, and not necessarily by the individual’s genetic or physical traits. They also reject the view that people with disability necessarily have worse lives than other people.

Research shows that people without disabilities tend to think that people with disabilities are not satisfied with their lives. It can be difficult for a person with “typical” function to imagine themselves or their family members living with a disability and being satisfied with their lives. This may be because of social bias, a lack of lived experience, or experiences with people with disabilities who grew up during times when support and services were not available.

But in fact, most people with disabilities, including Down syndrome, are very satisfied with their quality of life and say that they are happy. Research shows that people who do not have experience with Down syndrome tend to choose pregnancy termination because of a Down syndrome diagnosis. People who do have experience with Down syndrome choose to terminate a pregnancy after such a diagnosis less often. This means that women and couples should be as informed as possible about the conditions they choose to test for, and what it is like to live with them.

Those who criticize prenatal testing for harming disability rights believe that:

  1. Prenatal testing for disabling traits sends hurtful messages to the people living with the conditions that are being tested. This first point has been highly controversial in philosophical debates. Many people think that when an individual or a couple makes a personal medical choice, this hardly sends any “message”. This choice may express a preference to avoid raising a child with a disability, without expressing any negative attitude about individuals already living with such a disability.
  2. The existence and popularity of prenatal testing promote a views that stigmatize people living with the conditions that are being tested, such as Down syndrome. It also fosters negative attitudes towards parents who choose to have a child with Down syndrome.
  3. There is social value in genetic diversity and in the experience of disability. Following this line of thought, they believe that society would be losing something important if there were no more (or less) individuals living with Down syndrome because of individual reproductive choices.
  4. More resources should be directed towards integrating disabled people into the social and working environment, instead of trying to prevent disability by selective reproduction.
  5. Preference for ‘typical’ children is often based on misconceptions about what it means to live with disability or to care for someone with disability.

The “disability rights critique” is not generally directed at individuals who choose to use prenatal testing or abortion. Rather, it is directed at political leaders who create and maintain the social and economic conditions under which people with disabilities and their families live. The critics argue that these conditions often create barriers to opportunities, and these barriers encourage women and couples to make decisions to avoid disability.

A person may support social change to increase the resources and opportunities available to individuals living with disabilities and their families, and still prefer to avoid having a baby with Down syndrome or other disabilities.

Some people ask themselves whether in the current social circumstances, individuals feel truly free to make their individual choices. Do healthcare professionals have a negative bias towards people with disabilities and do they express this bias to parents expecting a child with Down syndrome? Do they feel limited due to lack of resources and support? Do they sometimes terminate a pregnancy because they are concerned that they will not be able to adequately care for a disabled child? Is promoting diversity on the one hand and offering prenatal testing on the other paradoxical? These are issues to consider and address as a society, so that people can accept or reject the offer of prenatal testing in a free and voluntary way, based on their personal preferences and values.

Attitudes towards having children

Some people think that all children are gifts. They invite parents to think about the reasons they want to become parents. They believe that parents who want to choose to have particular children (for example, without Down syndrome) view children as means to their own happiness. In this view, parents who welcome all children as they are, view children as ends in themselves.

Other people think that parents should choose the children that are going to be the happiest. These people think that “typical” people are happier than those with disabilities. They think that parents should use the options they have, such as prenatal testing, to make choices about what kind of child to have, so that their child will have the best possible life. This is called the “procreative beneficence” argument.

Learn more

The procreative beneficence argument

Some people argue that we have a moral obligation to use every available option to select a child that has better chances of living a good life. This could mean not only prenatal testing, but even costly technologies that allow to select which child to have, such as in-vitro fertilization (IVF) with pre-implantation genetic testing (PGT) of embryos to decide which one to implant in the uterus.

This argument is called ‘procreative beneficence’ – the view that we have a moral duty to select the child with the ‘best’ chances of a good life. Those who support this view admit that other considerations can be more important than this ‘obligation’ to select the child with the better chances. For example, the costs and health risks related to reproductive technologies such as IVF could justify not using them. Likewise, if pregnancy termination is not an acceptable option for a woman or couple, they may also decide not to fulfill their so-called ‘obligation’.

The argument of ‘procreative beneficence’ raises questions about what it means to have a ‘better life’. How do we define health and illness, capacities and disability, and the good life? And who gets to decide what these things mean? For example, from their own point of view, people with Down syndrome, or with other disabilities, do not necessarily have a worse life than others.

‘Procreative beneficence’ is also problematic because it raises the question of who actually benefits from it. It would be strange to argue that a fetus with Down syndrome ‘benefits’ from not being born. The life of the child it could become is unlikely to be so bad that it would have been better for him/her not to be born at all.

But once this fetus is ‘screened out’, if the woman conceives again, another fetus ‘benefits’ and a different child is born. From this perspective, terminating a pregnancy does not benefit the individual that is being ‘screened out’, except in cases where the disease or condition lead to such terrible quality of life, that it is better not to be born at all. For example, some argue that Tay Sachs disease is so awful, considering there is no cure and it leads to an early painful death, that a baby is better-off not being born at all, than being born with Tay Sachs.

Some people feel that they should select a ‘healthier’ embryo/fetus based on the interests of their existing children. They feel it would be unfair to burden them with a sibling that requires more care and support. Some people also feel that it is their own lives that would be made considerably worse if they had a child with special needs. Some people would say that the birth of a healthier or an intellectually typical person is simply “better” in itself than the birth of a person with health problems or a person with intellectual disability.

These beliefs are very personal, and these perceptions of disability are very subjective. Research does not show that families raising a child with special needs necessarily struggle more than other families.

Some other supporters of prenatal testing and other forms of selective reproduction argue that it is better for society to avoid the birth of people with significant needs. They argue that it is a good thing to help society become healthier.

This type of thinking has been historically termed “eugenics” – a desire to improve the gene pool of a given society. In the past, eugenic projects have guided policies that were discriminatory, unfair, and even violent, including policies such as forced sterilizations. Eugenics ideas ended up underlying the Nazi ideology and led to the mass murder, during World War II, of millions who were deemed ‘genetically unfit’.

Today’s supporters of prenatal testing distance themselves from such ideas. They make it clear that prenatal testing is meant to be used (or not) by individuals for the benefit of individuals, not societies. This is sometimes called ‘liberal eugenics’, because it focuses on the choices made by individuals, not policies that are promoted or enforced by governments. Yet, the historical shadow of eugenics remains and makes some people uncomfortable about the idea of ‘selecting children’ because it can be difficult to distinguish between social circumstances and individual choices.

References

See the references

Kaposy, C. (2013). A disability critique of the new prenatal test for Down syndrome. Kennedy Institute of Ethics Journal, 23(4), 299-324.

Rapp, R. (1988). Moral pioneers: women, men and fetuses on a frontier of reproductive technology. Women & health, 13(1-2), 101-117.

Rothman, B. K. (1986). The tentative pregnancy: Prenatal diagnosis and the future of motherhood (Vol. 1). New York: Viking.

Savulescu, J. (2001). Procreative beneficence: why we should select the best children. Bioethics, 15(5‐6), 413-426.

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Decisions after a positive diagnosis

Version française

After a positive prenatal testing result, you may consider whether you wish to continue or to end your pregnancy. This decision should be free and informed, meaning you should not feel under external pressure when you make it and you should have all the information you need to make it. You may want to learn about different topics to make your choice:

      • The condition that was diagnosed
      • The experience of families living with this condition
      • The resources available in your area for people with this condition
      • The pros and cons of terminating the pregnancy

Doctors and midwives give you information to help you make these decisions. They should not put pressure on you regarding your choice.

Resources like this website and local advocacy groups can be helpful to find more information.

In this section we talk about beliefs and realities regarding this choice. Then, we talk about these options:

Myths regarding decisions after diagnosis

Myths Reality
I must have an abortion because my result is positive. Abortion is a personal choice.
The government pays for testing and abortion. This means that we should abort babies with Down syndrome. The government pays for testing and abortion to make access equal for those who want to use them. It does not mean that using them is a better choice.
Having a baby with Down syndrome will make my life worse.
 Most parents of people with Down syndrome report being happy.
Having a baby with Down syndrome will make the life of my other children worse.
 Most siblings of people with Down syndrome report being happy.
I might regret having a baby with Down syndrome. Regret for having a baby with Down syndrome is very rare.
I might regret aborting a baby with Down syndrome. Regret for aborting a baby with Down syndrome is very rare.
Abortion could make me infertile.
An abortion done by a health care professional would not make you infertile.
Aborting and raising the child with Down syndrome are the only options. Adoption is also an option.

Raising the child with Down syndrome

Most people with Down syndrome live happy lives. Their parents and siblings also tend to be happy. These families may face challenges that are different from other families. However, regret for choosing to have a baby with Down syndrome is rare.

About half of children and adults with Down syndrome have some medical issues related to their heart or gut, but most are treatable in the first year of life. Many of them are very healthy.

People with Down syndrome have intellectual disability. This means that they are not as independent as other people. Some of them are just a little bit slower. Others have more serious challenges. This usually does not prevent them and their family from being happy. Most adults with Down syndrome need to live with other adults. However, some live on their own. A few  finish high school, go to university, have jobs, get married or drive a car. However, some have a hard time expressing themselves throughout their life.    

You can consult the “Down syndrome” section for detailed information on Down syndrome and life with Down syndrome.

Preparation for raising a child with Down syndrome

Some people use prenatal testing to find out in advance if their baby has Down syndrome. This allows them to get ready for raising a child with special needs. They may want to read about Down syndrome. They may also want to get in touch with other families who have a member with Down syndrome. Finally, they may want to change their birth plans because the risk of complications is a bit higher when the baby has Down syndrome. Support from social services, when requested, will only be available after the birth of the baby with Down Syndrome.

The choice to prepare for the birth of a baby with Down Syndrome is a personal choice. There is no right or wrong choice.

Learn more about medical and emotional preparation

For people who choose to continue a diagnosed pregnancy, prenatal screening and/or diagnosis provide the possibility of preparing for the birth of a child with Down syndrome or another condition. Such preparation may include medical aspects and day-to-day aspects.

Medical aspects

Before outlining the medical aspects, it is important to note that not all pregnancies with Down syndrome have medical complications that require interventions shortly after birth. Still, babies with Down syndrome are more likely than other babies to have certain medical issues.

Miscarriage occurs more often in pregnancies where the fetus has a genetic condition than in other pregnancies. Such pregnancies are also more likely to be complicated by problems such as growth restriction (when the fetus grows more slowly than it should inside the womb). Therefore, when there is a positive prenatal diagnosis, the pregnancy may be monitored more closely.

Babies born with Down syndrome are more likely than most babies to have some health problems that cause complications at birth or soon after, such as heart defects or intestinal (gut) obstruction. Therefore, women carrying a fetus with Down syndrome are offered extra follow-up services and some extra precautions at birth. For instance:

      • One or more extra prenatal ultrasound scans may be offered to find any abnormalities in organs (such as heart defect or gut obstruction) or growth restriction.
      • If an abnormality in an organ is detected, the choice of hospital for delivery is discussed. Health care practitioners may recommend a specialized center as opposed to a home birth, birthing homes or community hospitals. 
      • In case of a growth restriction, labor may need to be induced before the 39th week.
      • After birth, the baby may receive more attention from medical specialists, and might be kept in the hospital a little longer than after a typical birth, before being discharged home.

The precautions listed above may be suggested or recommended by health care providers. However, there may be differences in follow-up depending on providers, centers, regions, and more importantly, individual situations.

Emotional aspects

      • Having a baby with Down syndrome is not something most people expect when they decide to have a child. A prenatal diagnosis of Down syndrome often comes as a surprise and people may have various needs and strategies to adapt to this new reality.
      • People may seek counseling or emotional support, not only to help them in their decision-making, but also after their decision is made. Many grieve the “typical” child they had expected. It may be difficult to imagine the life of a person with Down syndrome and one own’s life as a parent of a child with Down syndrome. Coming to terms with the fact that their child will have Down syndrome may require a period of adjustment. It is normal to go through a range of emotions, including negative ones.
      • The family may want to meet with other families living with Down syndrome. This helps to get a concrete idea of what might be similar and different about raising a child with or without Down syndrome. Other families can also be a source of practical information on services, programs, and day-to-day living.
      • Support and advocacy groups for people with Down syndrome and their families may also be good sources of information and support. They may also provide a sense of community and belonging.
      • Some parents can have the feeling of being pregnant with a ‘diagnosis’, not a baby. It is important to remember that they are still expecting a baby who will have their own personality and the same needs as any baby. Indeed, most parents of children with Down syndrome report that they find their child more similar to most children than different.

Preparation for the day-to-day aspects of having a child with Down syndrome and possible medical complications can be reassuring for some people. However, it does not mean that it is necessary to prepare in any special way for the birth of a child with Down syndrome. In fact, many cases remain undiagnosed until birth and this does not prevent families from flourishing. Families welcome children with or without Down syndrome, with or without preparation.

Adoption

Adoption is also an option. Babies with Down syndrome find a home as quickly as other babies. Babies with Down syndrome go through the same steps as other babies placed for adoption. Some adoptive parents wish to adopt a baby with special needs.

There are resources to guide people in the adoption process. If you want to find out more about this option, you can contact:

Abortion (terminating the pregnancy)

Abortion is a personal choice. Women should always be allowed to make this choice freely and with all the information they need. This is also true when this choice is made because the baby has Down syndrome. Healthcare professionals and families should not put pressure on women to abort. The government pays for prenatal testing and abortion to make sure that those who want to use them have equal access. It does not mean that using them is a better choice. The government also pays for services for those who choose to have the baby. However, the services offered and the ease of access varies depending on regions.

Abortion is legal in Canada. Women do not have to give a reason for choosing abortion. Some women need to travel to a larger city or another province to get an abortion.

Abortion in the first trimester

Most abortions are done because the woman does not want to be pregnant. These abortions are usually done early in the pregnancy. In the first trimester, abortion can be done by taking a pill. However, in most cases, the diagnosis of Down syndrome is not confirmed until after the first trimester, so abortion by taking a pill is usually not an option. It can also be done by a simple procedure at the doctor’s office. The doctor “vacuums” the fetus out of the womb.

Learn more about first trimester abortions (sensitive content)

1. Pregnancy termination by taking pills

In the first trimester, it is possible to end a pregnancy by taking pills. It takes a few days and it feels like a heavy period.

A first medication is given to stop fetal cells from growing and dividing, and to separate the placenta from the wall of the womb. A few days later, a second medication is given for the womb to contract and empty. The process takes a few days to complete. The termination can feel like a very heavy period. The woman may stay home during the procedure, but a follow-up appointment is required to ensure that the termination is complete to avoid complications.

In some cases, the termination is not complete (some tissue is left in the womb). In these cases, it would be necessary to perform dilatation (slight widening of the cervix) and curettage (scraping of the wall of the womb from content).

2. Vacuum aspiration and curettage

In the first trimester, a doctor can end a pregnancy in a clinic or a hospital. The doctor uses instruments to remove the fetus from the womb. It takes less than 30 minutes with 2 hours of recovery. It feels like a heavy period.

Local anesthesia is provided, and the cervix is dilated (made wider) slightly to insert a small catheter (a tube). The content of the womb is suctioned through the catheter. If necessary, a curette (surgical instrument shaped like a scoop or a spoon) can be inserted to scrape the wall of the womb from content that could not be suctioned. Forceps (and instrument with pincers) are also occasionally needed.

The procedure takes 10 to 30 minutes and causes cramping similar to menstrual cramps. Recovery takes about 2 hours. A follow-up appointment is required to ensure that the termination is complete (that all the tissue has been removed). If the first attempt is not complete, this procedure may be done a second time, or it might be necessary to perform dilation and evacuation (see below).

3. Dilation with evacuation

In the first trimester, a doctor can end a pregnancy in a clinic or a hospital. The doctor uses instruments to remove the fetus from the womb. It takes less than 30 minutes with 2 hours of recovery. It feels like a heavy period.

One or two days before the procedure, a medication is given to dilate (make wider) the cervix, and/or a small device called laminaria is inserted in the cervix to cause progressive opening (dilatation), several hours before the procedure. Laminaria are thin and are about the length of a tampon.

A few hours later, sometimes the day later, local or general anesthesia is given. Women may be conscious or unconscious for the procedure. If a woman is conscious, she receives medication for pain relief, that also creates a sensation of ‘twilight sleep’. This means that she is awake, but sleepy, and will likely not remember the procedure. This is similar to what happens during colonoscopies or minor bone fracture surgery. The content of the womb is removed by vacuum aspiration. Curette, suction or forceps are also used. The procedure takes about 10-30 minutes. Side-effects include irregular bleeding for up to two weeks after and cramps similar to menstrual cramps.

Abortion in the second trimester

In the second trimester, abortion is more complex than in the first trimester. It can cause more pain, stress, and sorrow. It is usually done in the hospital. At week 14 to 23, some doctors use a surgical procedure called dilation and extraction. Others believe it is best to induce labor (see below).

Learn more about the procedures for second trimester abortions (sensitive content)

Dilatation and extraction

At week 14 to 23, doctors can end a pregnancy with a procedure called dilation and extraction.  The doctor uses instruments to remove the fetus from the womb. This method requires 2 to 3 days of preparation to open the womb.  The woman receives medication to prevent pain or to sleep during the procedure. It takes less than an hour. For the next 2 weeks, the woman may bleed and feel cramps.

Two to three days before the procedure, a medication is given to dilate (make wider) the cervix, and/or a small device called laminaria is inserted in the cervix to induce progressive opening (dilatation). Multiple luminaria may be inserted. Laminaria are thin and are about the length of a tampon. A more significant dilation is required than during first trimester procedures. This phase therefore lasts longer. 

On the second or third day, local or general anesthesia is given. Women may be asleep or awake for the procedure. If a woman is awake, she receives medication for pain relief, that also creates a sensation of ‘twilight sleep’. This means she is awake, but sleepy, and will likely not remember the procedure. This is similar to what happens during colonoscopies or minor bone fracture surgery.

With dilation and extraction, the fetus does not come out whole. It is usually not possible for parents to see and hold the fetus. An autopsy is also impossible. Some people prefer not to see the fetus. Others feel that it is an important part of grieving. This may influence the decision between dilation and extraction and labor induction. In either procedure, the fetus is sedated or an injection is used to stop its heart before the intervention. The fetus does not feel pain.

Abortions in the third trimester

In the third trimester, abortion is more complex than in the first or second trimester. It can cause more pain, stress, and sorrow. It is done in the hospital. In some cases, doctors will use dilation and extraction (see information in the section on second trimester abortions). Abortion in the third trimester may involve inducing labor.

Learn more about third trimester abortions (sensitive content)

Termination by labor induction

After week 24, going into labor can be needed to terminate the pregnancy. This means that the woman gives birth. The pregnant woman feels contractions and may even produce milk later on. This kind of termination is often more difficult to cope with.

This type of abortion is done in the hospital and it takes about 2 days. Labor is caused by medication as early as possible to make it easier for the woman. The woman gives birth as she would give birth to a live baby. She can have an epidural if she wants. Pain and duration of the process depend on the size of the fetus and whether it is the woman’s first baby. It is expected to be less painful and shorter than a live birth because the fetus is typically smaller. The doctor may use an injection to stop the baby’s heart before labor.

Learn more about what happens to the fetus during second and third trimester abortions (sensitive content)

With labor induction, the doctor may give the fetus an injection to stop the heart before labor. Other times, the fetus comes out alive and receives comfort care until it dies naturally. People may be given the choice between these options. It depends on centers, doctors and the fetus’ age. The lethal injection may be required depending on the gestational age and the center where the termination is done.

In cases where the fetus comes out alive, doctors always ensure that the baby does not feel pain. Staff is trained to support women and couples during and after the abortion.

Learn more about lactation after second and third trimester abortions (sensitive content)

Lactation (milk production) may occur after a second or third trimester abortion. Plans for dealing with this can be made ahead of time and may or may not include medication, depending on the woman’s desires. 

Emotional support

Abortions can trigger many feelings. After an abortion, some people experience grief or sadness. Most of the time, grief and sadness decrease over time. Regret after abortion is rare. People who felt free and informed at the time of choosing abortion tend to cope better with doubts, grief, and other negative feelings they may have.

Resources are available to support people before and after an abortion. Women’s health centers are good starting points to seek these resources. Online support groups exist as well.

Links for additional information on abortion

For more information on abortion:

In English: https://prochoice.org/patients/abortion-what-to-expect/

In French: http://cmq.org/publications-pdf/p-1-2012-09-01-fr-interruption-volontaire-de-grossesse.pdf

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Down syndrome

Version française

In this section, we talk about Down syndrome and life with Down syndrome. We discuss various topics:

Why does Down syndrome happen?

What difference does Down syndrome make in a person’s life?

Services

References

Why does Down syndrome happen?

Down syndrome is sometimes known as Trisomy 21. Trisomy means “three chromosomes”. Chromosomes carry genes. Babies receive their chromosomes at conception. Chromosomes usually come in pairs. We get 23 chromosomes from an egg (from the biological mother) and 23 matching chromosomes from the sperm (from the biological father). Trisomy occurs when a baby gets an extra chromosome from one of the parents.

Down syndrome, or Trisomy 21, occurs when the baby has three copies of the 21st chromosome instead of two copies. Most often, this happens purely by chance. Some rare cases are due to an arrangement in the mother’s or in the father’s chromosomes. It is never due to something that the parents did or did not do.

The chances of having a baby with Down syndrome increase as the mother gets older. However, it can happen at any age. In fact, most babies with Down syndrome are born to younger mothers, because younger women have more babies.

It happens more or less often in certain countries because of the age in which women get pregnant, the availability of prenantal screening and diagnostic, access to abortion, and unkown environmental and genetic factors. For example, it happens in about 1 in 800 births in Canada.

Learn more

Down syndrome and maternal age:

Incidence of Down syndrome means the number of babies born with Down syndrome. An incidence of 1 in 950 means one baby out of 950 is born with Down syndrome. Source: http://www.ndss.org/Down-Syndrome/What-Is-Down-Syndrome/
 

What difference does Down syndrome make in a person’s life?

In some ways, people with Down syndrome are just like other people. They have their own character that is not defined just by Down syndrome. They have desires and goals. They have meaningful relationships with other people. The difference that Down syndrome makes varies between people. It depends on the presence of health problems and on the extent of intellectual disability, which is not the same in everyone with Down syndrome. It also depends on the support they get, the opportunities they are given and their stimulation and social participation.

Learn more

The impact of Down syndrome depends on the person’s intellectual capacities, whether they have medical conditions, and the environment in which they live. Having medical conditions means that the person will require more medical visits and interventions. Just like other people, individuals with Down syndrome have strengths and weaknesses. Many families of people living with Down syndrome say that in most ways, they are just like other family members who do not have Down syndrome.

Early milestones

Nearly all children with Down syndrome learn to walk and most learn to speak. Children with Down syndrome often need speech and physical therapy to achieve these milestones. However, a minority of them never learn to speak. Most of those who cannot speak can learn sign language or use electronic devices to communicate.

Learn more

Almost all babies with Down syndrome have decreased muscle tone. This means that it takes them longer to become mobile and start walking and that they may require more stimulation. A large majority learn to walk before they turn four. Physical and occupational therapy can help with motor development.

Some people with Down syndrome speak very well while others are not able to speak at all. Most can be understood but might speak more slowly and/or less clearly. Speech therapy can help in maximizing speech capabilities. Some individuals with Down syndrome with limited verbal skills use a computerized keyboard to communicate effectively. Speech capabilities do not necessarily reflect cognitive capabilities.

School participation

Children with Down syndrome regularly attend school. Most children with Down syndrome receive special education services. Some receive these services in a regular class (inclusion), and some receive services in a small group setting for children with special needs. A few reach university.

Learn more

Children with Down syndrome usually attend school. They may be included in a regular or in a special education class. This decision is made by the parents and school staff and depends on the intellectual capabilities of the child, the school’s resources, and the parents’ and child’s preferences. School integration strategies are much more developed today than they were in past decades.

A few people with Down syndrome do live alone and/or drive cars. Increasingly more people with Down syndrome are going to college and finding meaningful employment in their communities. Individuals with Down syndrome may also participate in sports and leisure activities. Some perform well in the Paralympic or Special Olympics competitions. Participation in sports and leisure helps develop physical and mental abilities and promotes socialization.

Adult life

As adults, most people with Down syndrome continue to need at least some support from their families. Some of them live in their own residence with regular contact with family. Some of them stay with family members all their lives. They can also live in group homes or residences, which offer assistance for activities of daily living.   Most people with Down syndrome can work in some capacity, but some areas are behind in offering opportunities and supports for them. Some people with Down syndrome have regular jobs and some find work through special programs. Some cannot work. A few can drive a car. Most women with Down syndrome are fertile (they can have biological children) but most men with Down syndrome are infertile (they cannot have biological children). People with Down syndrome can have a love life. They have preferences and dreams just like other people.

Learn more

Most individuals with Down syndrome require at least some degree of assistance in adult life. Some may live on their own but require help with finances and emergencies. Others may require supervision on a continuous basis. They may live in group-homes or stay with their parents or other family members. Some may live in long-term care facilities.

Experiencing disability

People with Down syndrome and their families also have good days and bad days, like most people. Their struggles are often due to health problems. Biases against them and access to supports and services can also be a strain. Disability itself is usually not the main source of struggle. In fact, most people with Down syndrome say they are happy.

Learn more

Research shows that people without disabilities tend to underestimate the life satisfaction of people with disabilities. It can be difficult for a person with “typical” function to imagine themselves or their family members living with a disability and being satisfied with their lives. This may be because of social bias, a lack of lived experience, or experiences with people with disabilities who grew up during times supports and services were not available. Yet, a large majority of people with disabilities, including Down syndrome, report being happy and satisfied with their lives.

Family life

Most of their siblings and parents also are pleased with their life and family ties. Many of them feel that their loved one with Down syndrome makes them a better person.

Learn more

Many people assume that having a child with Down syndrome will have a negative impact on their family functioning. This might be because of people’s expectations regarding the special requirements for care and support. Some studies did find a negative impact of Down syndrome on quality of life, often when families did not receive needed supports.

However, other studies show that children with Down syndrome often have a neutral or positive impact on family life. Parents-child and sibling relationships are just as gratifying and challenging in families living with Down syndrome as in other families. One study found lower divorce rates in couples who raise a child with Down syndrome.

Research shows that siblings of children with Down syndrome are well-adjusted and have very developed interpersonal and caring skills. They also value positively their relationship with their sibling with Down syndrome.

It is not possible to know in advance the severity of the intellectual disability, developmental delays, and medical conditions. However, there is no direct relationship between the severity of these issues and feelings of parents (positive or negative) about the experience of parenting a child with Down syndrome.

It is also impossible to know in advance which parents and families will adapt more easily and which will struggle more. The experience of life with Down syndrome is as diverse as the experience of life without it. Pregnant women and expecting couples can learn about Down syndrome and try to imagine themselves and their family in that situation.

Life expectancy

People with Down syndrome have a shorter life span. Most people with Down syndrome live into their early 60’s with access to good medical care.

Learn more

With ongoing improvement in care and management of medical complications, the life expectancy of individuals with Down syndrome has now reached 60. Around that age, many people with Down syndrome may develop dementia and die from health conditions such as heart problems or cancer.

Medical conditions

People with Down syndrome are more prone to having certain health problems. Heart defects and digestive tract issues are among the most common problems. Many of these problems require surgery. The success rate for the surgeries is very high. People with Down syndrome are also more prone to have problems with their thyroid and thyroid conditions are now easily treated with medicine.

People with Down syndrome often have low muscle tone and lax ligaments. This means that they can become very flexible. However, it also makes them more prone to joint injury. People with Down syndrome also often have decreased hearing and sight. They also have a higher risk of developing leukemia . About 1% of people with Down syndrome develop leukemia in childhood,   However, they respond better to treatments than people who do not have Down syndrome. Finally, people with Down syndrome have a higher risk of developing Alzheimer’s. About 50% show signs of Alzheimer’s disease by the age of 50.

It is not always possible to know in advance which medical problems a baby with Down syndrome will have. Most people with Down syndrome have at least one of them and rarely all of them. They can usually be managed with medical support.

Possible pregnancy outcomes

Down syndrome can cause problems during pregnancy. Losing the baby is more common when the baby has Down syndrome. Pre-term birth and low birth-weight are more common. Heart problems in the newborn baby and stillbirths are also more common.

Learn more

Miscarriages happen in about 25% to 30% of pregnancies with Down syndrome, which is slightly more often than in typical pregnancies. This means that many women never find out that they had a pregnancy with Down syndrome. Stillbirths and complications during delivery are also more common in pregnancies with Down syndrome.

Intellectual capabilities

All people with Down syndrome have an intellectual disability, defined as limitations in intellectual functioning and adaptive behavior. Intellectual functioning include the ability to reason, learn, solve problems and understand complex ideas. Adaptive behavior include the ability to look after oneself, adapt to one’s environment, and practical and social skills.

The intellectual disability can be mild, moderate, or severe. For people with Down syndrome, it is most often mild or moderate. However, it is not possible to know in advance what level of intellectual disability an person with Down syndrome will have. To some extent, it depends on early stimulation. People with mild or moderate intellectual disability can learn to read and count. They may work and be independent in daily life. People with moderate intellectual disability need more guidance in daily life. They can learn basic self-care. People with severe disability need full time ongoing support.

Learn more
  • IQ is a measure of intellectual functioning. The average IQ in the general population is about 100. About two thirds of people have an IQ between 85 and 115.
  • Mild intellectual disabilityis used to describe the mental capabilities of a person with an IQ between 50 and 70. A moderate intellectual disability describes an IQ between 35 and 50. A severe intellectual disability refers to an IQ between 20 and 35. On average, people with Down syndrome have an IQ of 50, ranging between 30 and 70.
  • Individuals with Down syndrome often have better adaptive behavior compared with their intellectual functioning. They function better in daily life and social situations than their IQ score would predict.

Distinct physical traits

People with Down syndrome share some noticeable physical traits. They tend to be shorter than average. Their head, ears, mouth, hands, and feet also tend to be small. Their noses are a bit more flat, and their eyes have more of an almond shape. However, people with Down syndrome mostly resemble their parents and family members.

Services

In Canada, the services offered to families living with Down syndrome vary from province to province. Municipalities and support organizations may also offer various types of assistance locally.

Down syndrome associations may help you identify services in your region. To find out more about Down syndrome organizations in Canada, click here. 

Other online resources exist, such as:

Lettercase.org (based in the United States) : lettercase.org

Down syndrome pregnancy (based in the United States): https://downsyndromepregnancy.org/

Down Syndrome Diagnosis Network (based in the United States): https://www.dsdiagnosisnetwork.org

Down Syndrome Clinic to You (available world wide): dsc2u.org

References

See references

Foley, K-R.  Dyke, P. Girdler, S. Bourke J.  & Leonard, H. (2012) Young adults with intellectual disability transitioning from school to post-school: A literature review framed within the ICF, Disability and Rehabilitation, 34:20, 1747-1764, DOI: 10.3109/09638288.2012.660603

Savva, G.M., Morris*, J.K., Mutton, D.E. Alberman, E. (2006). Maternal age-specific fetal loss rates in Down syndrome pregnancies. Prenatal Diagnosis, 26:499-504.

Sansone, S.M., Schneider, A., Bickel, E. et al. Improving IQ measurement in intellectual disabilities using true deviation from population norms. J Neurodevelop Disord 6, 16 (2014). https://doi.org/10.1186/1866-1955-6-16

Scott, M., Foley, K.R., Bourke, J., Leonard, H & Girdler, S. (2014) “I have a good life”: the meaning of well-being from the perspective of young adults with Down syndrome, Disability and Rehabilitation, 36:15, 1290-1298, DOI: 10.3109/09638288.2013.854843

Sheets, K.B., et al., Practice guidelines for communicating a prenatal or postnatal diagnosis of Down syndrome: recommendations of the national society of genetic counselors. J Genet Couns, 2011. 20(5): p. 432-41.

Skotko, B. G., S. P. Levine and R. Goldstein (2011a). “Having a brother or sister with Down syndrome: perspectives from siblings.” American Journal of Medical Genetics. Part A. 10(59).

Skotko, B. G., S. P. Levine and R. Goldstein (2011b). “Having a son or daughter with Down syndrome: perspectives from mothers and fathers.” American Journal of Medical Genetics. Part A. 10(47).

Skotko, B. G., S. P. Levine and R. Goldstein (2011c). “Self-perceptions from people with Down syndrome.” Am J Med Genet A. 155a(10): 2360-2369.

Thomas K, Girdler S, Bourke J, et al. Overview of health issues in school-aged children with Down syndrome. Int Rev Res Ment Retard 2010;39:67–106.

National Down Syndrome Society. URL:  http://www.ndss.org/. Page accessed on September 28, 20221

Canadian Down Syndrome Society. “Can a person with Down syndrome live on their own?”. URL:  https://cdss.ca/down-syndrome-answers/can-a-person-with-down-syndrome-live-on-their-own/. Page accessed on September 28, 2021.

Canadian Down Syndrome Society. “Can a person with Down syndrome get their driver’s licence?”. URL:  https://cdss.ca/down-syndrome-answers/can-a-person-with-down-syndrome-get-their-drivers-licence/. Page accessed on September 28, 2021.

Canadian Down Syndrome Society. “Down syndrome answers”. URL:  https://cdss.ca/down-syndrome-answers/. Page accessed on September 28, 2021.

United Nations. “World Down Syndrome Day, 21 March?”. URL:  https://www.un.org/en/observances/down-syndrome-day. Page accessed on September 28, 2021.