It has been discovered that a blood sample taken from the mother at any time from early pregnancy can be analysed for cell free fetal DNA, which is essentially a marker in the mother’s blood of the DNA of the baby. The result of the simple blood test (SAFE), taken at 10 weeks or later has a sensitivity for the detection of Downs syndrome greater than 99%, 99% of Edwards syndrome and 99% of Patau’s syndrome, with a false positive rate of less than 0.1% which will hugely reduce the need for invasive testing by CVS or amniocentesis. This is great news for couples because it reduces the risk of miscarriage from invasive testing. It is important that an ultrasound scan is performed just before the blood test to confirm the pregnancy, and to check that the mother is not carrying twins or more. The SAFE test can be used to check twins with a detection rate of 95%, and if a vanishing twin has occurred. The SAFE test can be used if the pregnancy is conceived with donated eggs.
This is now one of the most accurate non invasive tests to detect the chance of a chromosomal abnormality in a pregnancy (Positive predictive value 'PPV' greater than 99% for Downs, Edwards and Patau Syndrome).
For the last ten years doctors have been using the results of the Nuchal Translucency Scan to advise pregnant women and their partners on their risk of having a baby with Downs syndrome, or other abnormalities. The Nuchal Translucency Scan looks at the skin fold on the back of the baby’s neck at about 12 weeks. This has been further refined by looking at the nose bone of the baby with an additional blood test to identify two pregnancy hormones. This is the combined test and has achieved a positive predictive value of about 84%. Women with a high risk Nuchal translucency scan have an option to proceed to chorion villous sampling (CVS) or amniocentesis. These are invasive tests that carry a miscarriage risk of about 1:100. This is changing. The SAFE blood test has become available.
Anyone who wants extra reassurance about the normality of the pregnancy can have the test. Women who may need it are those who are anxious about their baby having a chromosomal abnormality such as Downs, Edwards or Patau's syndrome, older women (particularly over 40 years) and those who have already had a chromosomally abnormal pregnancy often opt for the test. Those who are at particular risk of miscarriage should they have an amniocentesis or chorionic villous sample also find the test very attractive as it avoids an invasive procedure.
The result is available within 3-7 days, the normal turnaround time is 5 days. There is less than 1% chance that insufficient DNA is obtained. This is not a positive or negative test: it is an unsuccessful test. An offer of a repeat test is made free of charge. This is usually successful. In rare circumstances the result can take longer than 7 days. We understand it can be a stressful time waiting for results and we will endeavour to communicate any delays to our patients as soon as we receive information from the laboratory.
The result is expressed as a probability. It is a screening test and not a diagnostic test. A result form of a low risk test is shown below. A low risk test result gives a risk of a chromosomal problem of less than 1:10000-1:1000000. A high risk result gives a risk of greater than 99%. A high risk result does not confirm that the baby has the chromosome abnormality. An amniocentesis or chorionic villous sampling is necessary to give a diagnosis. The couple are counselled about this.
The test is currently £500 including the ultrasound scan when done on a weekday. Appointments after 5.00pm will carry a £30 surcharge. If you would like to come in on a Saturday the cost is £550.
Depending on how many weeks pregnant you are, you will still have the opportunity to have a 12 week scan privately or with the NHS. The focus of the 12 week scan will change as you will already have the result of the Downs syndrome test, so the 12 week scan will look at the baby in detail for structural abnormalities (these may exist without a chromosomal abnormality). You will still have the opportunity to have the later scans, such as the 20 weeks scan, as before. If the Harmony test is low risk then it is important that the person conducting the 12 week scan is aware of this. If the test is high risk then you should return to The Birth Company or a good NHS unit for further counselling.
Yes. Structural abnormalities such as Spina Bifida, heart defects and a poorly growing baby will only be seen on scans and often not until later scans. These scans should still be undertaken.
This new test has been developed by Premaitha Limited http://www.premaitha.com and is processed by St Georges University Hospital https://www.stgeorges.nhs.uk/service/maternity-services/fetal-medicine-unit/the-safe-test/
' Professional and reassuring 'Helen Campbell
The sonographer was ready as soon as I arrived, and she was extremely calming, personable and professional. The scan and blood test where efficient without feeling rushed and all very easy. These appointments can feel uneasy and make you feel anxious but I felt reassured and in professional hands the whole time
I saw Kate throughout my first pregnancy and am now doing so again with my second. She is absolutely amazing, she explains everything really clearly, and has answered all sorts of bizarre questions and worries I have had. On top of being clinically excellent she is also just the loveliest person and always a pleasure to see.Sarah Elliott
We had the harmony test with the Birth Company and had a reassurance scan with sonographer Kirsty McGarry who was absolutely lovely and really put our minds at rest. We had been scared by our NHS dating scan and left feeling like there was something wrong. We explained the situation and was treated very professionally and with good care. Also speedy appointments also as I had phone in the morning and got an appointment by afternoon. So thankful.Ashley and Tom
Really friendly, efficient service. Great experience overall. Had the Panorama. My appointment was with Kate who was absolutely fantastic. The results came really quickly. Have a comparison with private healthcare elsewhere and must say that The Birth Company was just how I would like to be treated when I pay for medical services - attentively, calmly, friendly, in a pleasant environment that doesn't look like hospital. Top marks!Anna
' Efficient, friendly and always on hand to provide last minute appointments 'Hannah Murphy
The Birth Company has been excellent, providing timely scans and blood tests during my IVF treatment abroad. Staff are always friendly and extremely efficient. I would highly recommend coming here.
' Professional and friendly 'Lyndsey Dilla
When I first contacted the Birth Company I spoke to Danielle. She was fantastic. She went above & beyond to put me at easy & make the journey from Kent as stress free as possible. Every staff member that myself and my husband have come into contact with have been approachable, professional and friendly. Kate scanned me the first time and put me completely at easy. Lisa on reception is professional and very approachable. Highly recommended
' Highly recommended 'Emelie
Donald was so lovely! I was so nervous as I have a bad history and he was super quick and confirmed my baby's heartbeat as quickly as he could. He spent time showing me the baby and the anatomy and it was the best money I have ever spent! The reception girls were lovely too - considering they deal with babies day in day out they were super excited for me! Thank you so much one and all! If only I lived in London and could have all my scans with you!
Great Portland Street