Pregnancy / 21 March, 2017 / Leo Bamford
These non-evasive pre-natal tests are something new to me. Six years ago when I had my last, this was not something on offer, and if you needed further testing, they definitely weren’t non-invasive!
The aim of the SAFE test Panorama and Harmony tests are to find out whether your unborn baby has a chromosomal abnormality, such as down’s syndrome, without the miscarriage risk associated with the CVS or amniocentesis. The tests are most known for detected down syndrome, Trisomy 21, but it also gives information for other fetal chromosomal abnormalities, Trisomy 18 (Edwards syndrome) and Trisomy 13 (Patau’s Syndrome).
Now you may ask, how on earth do they do this? And the thing that got me is how early they can detect these things. Basically, they analysis fatal cell-free DNA circulating in your blood and results can be as quick as up to five days.
The way this is done is by a simple blood test, that is sent off for a very accurate screening test. The test identifies more than 99%, but not all of the foetuses with down syndrome, 98% with Trisomy 18, and 80% with Trisomy 13. If it shows there’s a high risk of abnormality in the foetus, the main problem is, is that it doesn’t mean that the foetus definitely has one of these defects, and that is when usually further testing is required, by way of CVS or amniocentesis.
Even if you do have one of these tests, a scan is still necessary to exclude other problems. These tests can be performed in most pregnancy of at least 10 weeks gestational age, although not currently available in egg donor pregnancies, multiple press, or where the egg donor is unrelated to the recipient, or for when the detection of partial trisomies.
I had the test done at Ultrasound Diagnostic Services at exactly 10 weeks, although I was told they were pretty much the same, I went for the SAFE test where the blood is tested in England so it comes back within a week. Download the pdf for more information.
The most incredible thing to me, in only 5 days, at only 10 weeks pregnant, I would know the sex of my baby. Through scans, you never really know until you’re actually in the delivery room, so to be told the sex so early on is quite amazing.
Ellie had the Harmony test at the Fetal Medicine Centre, which if you have this done at 10 weeks, comes in a package that includes the viability scan and harmony test at 10 weeks and nuchal test at 12 weeks. It also includes CVS if the harmony test suggests that the fetus has trisomy 21, 18 or 13. This Harmony test takes 2 weeks to come back as bloods are sent to the US to be analysed.