Safer test, shorter wait as new Down’s screening comes to St George’s
St George’s University Hospitals NHS Foundation Trust announced today that it will begin offering an in-house, non-invasive prenatal test (NIPT) for pregnant women in the UK. The test will help expectant mothers to understand the chance of their unborn baby having Down’s syndrome, Edwards’ or Patau’s syndrome.
The trust revealed in March this year that it was joining forces with British firm, Premaitha Health to bring this new screening to St George’s.
Before this, pregnant women in the UK could only access NIPT privately, with blood samples being sent either to the US or China. Not only was this costly, but it also carried a waiting time of up to two weeks for results which are pivotal in helping parents make decisions about their pregnancies.
St George’s screening test will be called ‘the SAFE test’ and St George’s will be the only trust to offer NIPT to expectant mothers through the NHS. Based on Premaitha Health’s IONA® test, the SAFE test analyses a small sample of the mother’s blood to correctly identify over 99% of Down syndrome, Patau’s and Edwards syndrome.
The SAFE test carries a range of benefits:
Safe: The greatly reduced false positive rate of the SAFE test means that fewer pregnant women will undergo invasive procedures such as amniocentesis and chorionic villus sampling (CVS), which are stressful and carry a risk of miscarriage.
Accurate: The SAFE test correctly identifies over 99% of Down syndrome,Patau’s and Edwards syndrome.
Fast: Women who undergo the SAFE test will receive their results in five days, compared with the 10 to 14-day turnaround time when their samples are sent to the US or China.
Effective: The analysis through the SAFE test will include both measurements of placental material and take into account the pregnant woman’s specific pre-test chance for genetic conditions.. By combining these two parameters the SAFE test maintains a high detection rate for a greatly reduced false positive rate.
St George’s is committed to making the SAFE test available to our patients as soon as possible. We have partnered with Premaitha to launch a focused NHS service from June and will open a fully commissioned screening laboratory in September 2015.
The focused service will be available to all pregnant women referred to St George’s to receive further care after receiving a NHS “high risk” combined test result.
The women will have the choice to undertake either a CVS or the SAFE test – as clinically appropriate.
Professor Basky Thilaganathan, Consultant Obstetrician at St George’s commented, “This is great news for the trust and for pregnant women in the UK.
“NIPT has the potential to make a huge difference to the care that clinicians can offer to pregnant women. Too many have been through the anxiety and discomfort of invasive procedures after receiving false positive results from the combined test – the SAFE test gives us the accuracy and reliability to reduce this number significantly.
“We are very happy to be able to partner with a UK innovator like Premaitha to create an UK Centre of Excellence using the IONA® test – currently the only CE-marked NIPT test.”
Patient questions answered…
When is the IONA® test available?
The IONA® test will be available at St George’s NHS Foundation Trust Hospital from 1st June 2015. Please ask your healthcare provider for further information.
Who will be eligible to receive the IONA® test through St George’s? Is it only pregnant women in London? High chance pregnancies only?All women will be able to have the SAFE/IONA test. It will be undertaken free-of-charge for high-chance women (>1:150 chancefor Down, Edward or Patau syndrome) referred for further care in the Fetal Medicine Unit at St Georges. Low chance women (and high chance women who have not been referred to St Georges) will be able to self-pay to have the SAFE/IONA test – either through their own hospital or through private clinics. Please speak with your local obstetrician about options.
How accurate is the IONA® test?
The IONA® test is very accurate. It identifies over 99% of babies with Down’s syndrome, Patau’s syndrome and Edwards’ syndrome.
What is the false positive rate?
Less than 1% of pregnant women may receive a high chance result from the IONA® test and then go onto to have a follow up invasive test which confirms that the fetus is not affected with trisomy 21, 18 or 13.
How is the sample taken?
A simple blood sample is taken from your arm by a healthcare professional after you have been pregnant for at least 10 weeks.
How does the IONA® test work?
During pregnancy the placenta leaks fragments of DNA that circulate in the maternal bloodstream. The IONA® test uses a technology to count these DNA fragments in your blood to identify certain chromosomal conditions in the pregnancy.
What is the current screening offered by the NHS?
Currently the NHS offers pregnant women the combined test which includes a fetal ultrasound and blood test performed at about 12 weeks into your pregnancy. The ultrasound looks at multiple aspects of the developing fetus, but particularly at the skin fold at the top of the spine where it meets the skull. The blood test measures the levels of two hormones: hCG and PAPP-A. The current combined test has a 90% detection rate and ~5% false positive rate.
Is the IONA® test replacing a 12 week scan?
No, it is recommended that you still have this dating scan at 12 weeks to assess the baby’s growth and development. The IONA® test or any other NIPT will not replace the 12 week ultrasound dating scan.
Is the IONA® test 100% conclusive?
No, NIPT including the IONA® test cannot be 100% accurate, it is a screening test, not a diagnostic procedure, which estimates the probability that the fetus is affected with Trisomy 21, 18 or 13. High chance results should be confirmed with a follow-up invasive diagnostic procedure such as an amniocentesis.
Is the IONA test safe?
Yes, due to the fact that the IONA® test is non-invasive, there is no associated risk to the mother or fetus. The only risks are those associated with venepuncture.
How long will it take to get the results?
Once the sample is received at the laboratory it can take 5 working days to perform test. The data from the laboratory test entered into the IONA® analysis software and an easy to interpret result report is generated and given to your healthcare professional such as a consultant or midwife.
How are the IONA® results reported?
Lowchance: means that it is very unlikely your pregnancy is affected by trisomy 21, 18 or 13.
High chance: means that your pregnancy is at increased chance for trisomy 21, 18 or 13 and a follow up invasive procedure may be recommended by your healthcare provider.
No result: Very occasionally the laboratory is unable to produce a result from the blood sample as they are unable to obtain enough placental DNA from the blood sample. You may need to come back to the hospital to repeat the test.
How will I receive my results?
If you receive a “low chance” result for trisomy you will receive a confirmatory letter / email from the hospital. However, if you get a “high chance” result you will be contacted by your midwife / consultant and be asked back to the hospital for a follow-up invasive test and genetic counselling.
Does the IONA® test report the sex of the fetus?
No, the IONA® test does not report on the sex of the fetus. The IONA® test estimates the probability that a fetus is affected with Down’s syndrome (trisomy 21), Edwards’ syndrome (trisomy 18), Patau’s syndrome (trisomy 13).
Who can have the IONA® test?
The IONA® test is available for all singleton and twin pregnancies (TBC) and for pregnancies conceived by spontaneous conception, surrogates or through IVF.
What are my options if I have a high chanceresult for a trisomy?
If you get a “high chance” result you will be contacted by your midwife / consultant, the next steps will be determined in consultation with your healthcare provider.