Screening for Down's Syndrome

Screening for Down's Syndrome

Between 11 and 14 weeks of pregnancy you’ll be offered a screening test for Down's Syndrome to assess your chances of having a baby with this condition.

Down's Syndrome on the NHS website

How the screening test is done

The test combines an ultrasound scan with a blood test. At the scan, the fluid at the back of the baby’s neck is measured and this measurement, combined with the results of your blood test are used to work out the chances of your baby having Down's Syndrome .

If you are more than 14 weeks into your pregnancy, you’ll be offered a different test. This test uses just a blood test and only tests for your chances of having a baby with Down's Syndrome.

Deciding not to have the screening test

The screening tests are completely optional and you don’t have to have them if you don’t want to. The important thing is that you understand exactly what the tests are and why they’re done before making your decision.

You can also choose to have screening for some of the conditions but not all of them. Talk to your midwife about your options.

If you choose not to have the screening tests, you can still have your ultrasound scan.

Getting your results

It’s important to remember that the results of your screening test only shows if there's a higher or lower chance of your baby may have Down's Syndrome. The test can’t tell you for certain if your baby has any of these conditions.

If you’re test results show that your baby is higher risk for Down's Syndrome, then you'll receive a phone call advising you within a few days. If your results are lower risk, you’ll be advised by post within two weeks.

Understanding your results

You'll be given your Down's Syndrome screening result as a statistical chance, eg 1 in 1000. In this example it means that out of 1000 women who had the same results as you (from the blood test and scan measurement) only 1 would have a child with the condition screened for.

If your result is lower than 1 in 150, your results are considered lower risk and no further testing will be offered. It is important to remember however that a lower risk results doesn’t mean that there is no risk at all.

Higher risk results

If your result is higher than 1 in 150, your results are considered higher risk your doctor and midwife will talk to you about your options. You may want to have further tests which can tell you for definite whether or not your baby has the condition that was tested for.

Non-invasive prenatal testing (NIPT) e.g. Harmony test

Using a blood sample taken from you, the Harmony test can give a strong indication of whether your unborn baby is at high or low risk of having Trisomy 21 (Down's syndrome), Trisomy 18 (Edward's Syndrome) or Trisomy 13 (Patau's Syndrome). This test can also indicate the baby's sex.

The test is over 99% accurate and can be carried out from when you’re 10 weeks pregnant. You can expect your results within one week.

The Harmony test is not usually offered as part of your standard maternity care. However, if you’re baby has been identified as high risk through other screening tests then you may be offered the Harmony test for a fee. The laboratory charge is approximately £300.

The Harmony test is available privately through some of the obstetric consultants.

Harmony test website

Jersey private patients

Having further testing

If your screening test shows that your baby has a higher chance of having a condition, or finds a possible problem, it can be a very upsetting and worrying time. Your specialist fetal medicine midwife will discuss your options with you.

These options will include further testing known as diagnostic testing, such as amniocentesis or chorionic villus sampling (CVS).

While invasive diagnostic tests are 100% accurate they do come with a small risk of miscarriage (1% to 2%).

You don’t have to have any further tests if you don’t want to. It’s your personal choice but it’s important that you understand what your options are before you make your decision.

Chorionic villus sampling (CVS) on the NHS website

Amniocentesis on the NHS website

If tests confirm that your baby has a condition

If further testing confirms that your baby has a condition, your specialist fetal medicine midwife will be there to answer your questions and tell you about all your choices and options.

Finding out that your baby has a condition can be extremely upsetting and worrying. You may be faced with the decision of whether to continue with your pregnancy or end the pregnancy with a termination. This is often a very difficult choice to make and you may feel differently from one day to the next.

Your consultant and midwife will be there to talk you about your decision and the charity ARC can also offer support.

No pressure will be put on your to make a certain decision and your consultant and midwife will support you in whatever choice you make.

ARC helpline

You can contact the charity Antenatal Results and Choices (ARC), which has information about screening tests and how you might feel if you're told your baby has, or might have, a problem.

The charity has a helpline that can be reached on +44 (0) 845 077 2290, or +44 (0) 20 7713 7486, Monday to Friday, 10am to 5.30pm. Calls to the helpline are answered by trained staff, who can offer information and support.

ARC website

Continuing with your pregnancy

If you choose to continue, your pregnancy may be monitored by a consultant and you may have to attend extra appointments and scans to meet your needs and circumstances.
You may also be given the opportunity to meet with a paediatrician so that you can gain a better understanding of your baby’s possible condition after birth.

Continuing your pregnancy on the ARC website

Choosing to end your pregnancy

If you choose not to continue your pregnancy, your obstetrician and midwife will discuss the different methods available to end your pregnancy.

Depending on how far along you are in your pregnancy, you may have to be admitted to Delivery Suite to manage the end of your pregnancy safely. If this is the case, you will be given a private family room where you can have someone stay with you for support. Your midwives will make sure you receive the privacy and support you need during your time in hospital.

Ending a pregnancy on the ARC website

Support if you choose to end your pregnancy

Choosing to end your pregnancy can be very emotionally upsetting and physically draining. You might experience feelings of shock, grief, guilt and anger. Talking about your feelings can be a good way of processing your emotions and can help you feel better.

If you feel like you'd like to speak with someone about what you're going through, you can contact Jersey Hospice and speak with someone from their bereavement service.

The charity Antenatal Results and Choices (ARC) can also offer support and advice during this difficult time.

ARC website