Screening for Down, Edwards and Patau syndromes during pregnancy
Screening for Down, Edwards and Patau syndromes
As recommended by the UK National Screening Committee (UKNSC), we offer screening for Down, Edwards and Patau syndromes to all women between 11+2 and 14+1 weeks of pregnancy (the combined test) or 14+2 and 20+0 weeks (the quadruple test). There is no screening test available if you are found to be over 20 weeks pregnant, but if anything is seen on the detailed scan of your baby (fetal anomaly or 20 week scan) that could be associated with any of these syndromes, the sonographer will discuss this with you and you will be referred to a specialist to discuss them further.
These screening tests are optional. We would like you to be able to make an informed choice as to whether you want to screen for these conditions or not so please use the links and/or contact for more information and support.
NHS Fetal anomaly screening programme information
Antenatal Results and Choices (ARC)
- 0207 713 7486
- Down syndrome Association
- 0333 1212 300
- Down syndrome Norfolk
- Positive about Down syndrome
Edwards and Patau syndromes
- SOFT – Support Organisation For Trisomy 13/18
- 0300 102 7638
- Antenatal and Newborn Screening Midwives
- 01603 286802
Higher chance combined or quadruple test result
If your screening result shows a higher chance of any of these conditions you will be contacted directly to discuss the result and be offered non-invasive prenatal testing (NIPT) or a diagnostic test – either chorionic villus sample (CVS) or amniocentesis. NIPT is a blood test that’s a more sensitive screening test. A diagnostic test will tell you a definite yes or no and involves sampling the pregnancy to look at cells, either from the placenta or cells from the baby found in the amniotic fluid (the fluid the baby is floating in). Unfortunately CVS and amniocentesis do have a small chance of miscarriage so they too are optional.
You will get the opportunity to discuss this fully if you are contacted with a higher chance result. You may find the following links helpful:
- “Your choices after a higher chance result”
- Chorionic Villus Sample (CVS) – NNUH leaflet
- Amniocentesis – NNUH leaflet
Do the screening tests identify anything else?
One of the hormones measured in the Combined test is called Pregnancy Associated Plasma Protein-A (PAPP-A). Occasionally the blood test will show a low level of PAPP-A. This by itself does not put the baby at risk of having one of these syndromes, but we know that sometimes the baby can grow more slowly in later pregnancy. If this is the case you will be contacted directly and further appointments will be arranged later in pregnancy to check how your baby is growing.
One of the hormones measured in the Quadruple test is called Alpha-fetoprotein (AFP). AFP can be raised when there is a problem such as Spina bifida. If your level is higher, you will be contacted directly and offered an appointment for an ultrasound scan. An ultrasound scan allows us to check the baby in great detail and will usually identify the problem if there is Spina bifida. Most women with an increased hormone level will go on to have a baby without Spina bifida.