Non-Invasive Prenatal Testing for Down’s Syndrome

The NHS offer screening tests for Down’s syndrome, Edwards’ syndrome and Patau’s syndrome between 10 and 14 weeks of pregnancy. There is a new blood test being launched that’s safer and non-invasive. 

Down’s syndrome is a genetic condition that causes some degree of learning disability and certain physical characteristics. It also means a higher risk of other health problems such as heart disorders, thyroid problems, recurrent infections and hearing and vision problems. The condition is caused by an extra chromosome which is usually the result of a one-off genetic change in the gametes. 

Women who are over the age of 38 are more likely to have a child with Down’s syndrome and this number rises as more women choose to have children later in life. The screening tests currently in place show the likelihood of having a baby with Down’s syndrome but more tests would have to be done to confirm it. 

The screening test is available between 10 and 14 weeks of pregnancy. It’s a combined test as it involves an ultrasound scan with a blood test. It cannot harm the patient or the baby but it doesn’t tell you for certain if the baby has the condition. 

The current tests for higher-chance pregnancies are chorionic villus sampling (CVS) and amniocentesis. CVS is where a sample is taken from the placenta and tested during 11-14 weeks of pregnancy. Amniocentesis is where amniotic fluid (fluid from the womb) is tested between 15-20 weeks of pregnancy. These tests are quite invasive and have a small risk of miscarriage.

The new test will be offered to women deemed a high risk and will most likely increase the amount of women having the test due to it having no miscarriage risk. This could lead to a higher abortion rate.

Some of the reasons a woman might continue the pregnancy after diagnosis are:

  1. Religious beliefs – not wanting to experience abortion
  2. Previous fertility - may have struggled to get pregnant
  3. Seeing foetus on monitor and feeling movement or heartbeat
  4. Positive attitude towards Down's syndrome
Some of the reasons a woman might terminate pregnancy after diagnosis are:

  1. Perceived burden of a disabled child 
  2. Having a child with a reduced quality of life
  3. Prognosis being too uncertain
  4. Concerns of what will happen to the child after parents have died
  5. Negative attitude towards Down's syndrome
Down’s syndrome testing leads to ethical debate as it gives risk to women, couples, disabled people and the future society in terms of inequality. A child with Down’s syndrome can still lead a long, happy life with the help of increased services and support available. People believe the new testing will lead to less children with Down syndrome being born which will affect the community and how society views people with the condition. There are also lots of ethical debates around abortion with different people having different ideas to when life begins.


However, it is a woman’s choice to have the test and to have an abortion so there are ethical grounds to allow the test. The new test doesn’t harm the baby or the patient so it should be offered instead of the more unsafe methods. 

Overall, this is a very controversial topic but the new testing will be implemented soon instead of tests such as CVS. It has already been introduced in Wales.

Thank you for reading! I hope you found this interesting.

Written by Lizzie Nash

Sources
https://www.nhs.uk/conditions/downs-syndrome/
https://www.nhs.uk/conditions/pregnancy-and-baby/screening-amniocentesis-downs-syndrome/
https://www.theguardian.com/society/2016/oct/29/safer-downs-syndrome-test-nhs-pregnant-women-nipt
http://nuffieldbioethics.org/wp-content/uploads/NIPT-ethical-issues-full-report.pdf

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