Non-invasive prenatal testing (also called cell free fetal DNA screening) is essentially a blood test taken from the mother to look at the babies DNA to screen for chromosomal and genetic conditions.
The vast majority of NIPT tests available are performed from 10+0 weeks. The Panorama test offers testing from 9+0 weeks. It is ideal that you have a scan on the day or at least have had a scan within the last 14 days to confirm the gestational age, to count the number of babies (i.e singleton or multiple pregnancy) and to confirm that the pregnancy is developing normally (we will start to look for major anomalies from 10 weeks).
Ultrasound examination:
We will perform an ultrasound examination before taking the blood sample. In most cases this is an abdominal scan (from your abdomen/tummy) but sometimes the views are limited, and we will need to perform a transvaginal scan with your consent.
The reason for the scan is to confirm that the pregnancy is developing normally. Under the rare circumstance that a fetal anomaly is seen on scan, we will explain the findings and make recommendations on available choices. Sometimes NIPT is not the best test in these circumstances (because it is a screening test and not diagnostic), and we will guide you through the best options. The scan will accurately date the pregnancy (NIPT will not work if the blood is taken too early) and allow us to count the number of babies (about 1 in 80 mothers will be surprised to hear that they have more than one baby).
If you have had a scan performed within the last 14 days, we do not have to perform a scan if you wish.
Take a blood sample:
A routine blood sample is taken from your arm – the same as any other blood test.
NIPT can screen for a very wide range of chromosomal and genetic conditions.
NIPT is most often used to screen for:
The major advantage of NIPT is the very high detection rate with a very low false positive rate (<0.1%), without any risk of miscarriage. This means that the test will detect the majority of cases of these three common fetal aneuploidies and very few women will be given a high chance result (unlike the traditional Combined or Quadruple test offered in the NHS which has a lower detection and a false positive rate of about 3%.
Performance of NIPT compared to the Combined Test
Detection Rate (%) | False Positive Rate (%) | Combined screening DR (%) for 3% False positive rate | |
---|---|---|---|
Trisomy 21 | 99.7 | 0.04 | 86 |
Trisomy 13 | 99.0 | 0.04 | 84 |
Trisomy 18 | 97.9 | 0.04 | 72 |
One of our many strengths is that we are all consultants in Fetal Medicine and have both specialist and detailed knowledge about the tests available. We currently offer the PrenataSafe test, the Illumina test, and the Panorama Test and we are very happy to discuss which test will suit your individual needs.
PRENATALSAFE® 3 | PANORAMA | ILLUMINA | |
---|---|---|---|
Price | Starting price at £395 | Starting price at £395 | Starting price at £395 |
When | >10+0 weeks | >9+0 weeks | >10+0 weeks |
Turnaround time | 5 working days | 10 working days | 5 working days |
Laboratory Location | Surrey,UK | California, USA | London, UK |
Redraw rate | 2% | 2% | 2% |
Trisomy 21, 18, 13 | ✓ | ✓ | ✓ |
Twin pregnancies | ✓ | ✓ | ✓ |
Vanishing twin | ✓ | ✕ | ✕ |
Fetal sex (optional) | ✓ | ✓ | ✓ |
Advanced panel (optional with extra charge) |
✓ For more information, please check PrenatalSafe® 9 |
✓ | ✕ |