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What is Down’s syndrome?
Down’s syndrome is a genetic condition caused by a full or part of a third copy of chromosome 21 in the body’s cells. This usually happens by chance and is not caused by anything parents do before or during pregnancy. People with the condition can live healthy and fulfilling lives as part of their families and communities. Some may live independently, have jobs, be in relationships and socialise with minimal support. Children with Down’s Syndrome can attend a mainstream school and receive any additional support they require.
Most people with Down’s Syndrome will have mild to moderate learning disabilities. Some may have more complex needs. The amount of help and support they will need cannot be known before they are born. People with Down’s syndrome will receive regular heath checks throughout their life to ensure that any associated health issues can be picked up early and they can receive the care they need.
Older mothers are more likely to have a baby with Down’s syndrome, but this condition can also occur in women of any age. All pregnant women, no matter what age, can have the test.
You can visit these websites for further information and support:
You can also speak to your community midwife or screening midwife for further support.
What is Edwards’ syndrome?
A baby with Edwards’ syndrome has 3 copies of chromosome number 18 instead of 2. This affects the way the baby grows and develops; this is a rare but serious condition. This usually happens by chance and is not caused by anything parents do before or during pregnancy. Your chance of having a baby with Edwards’ syndrome increases as you get older, but anyone can have a baby with Edwards’ syndrome. Edwards’ syndrome affects how long a baby may survive. Sadly, most babies with Edwards’ syndrome will die before or shortly after being born. A small number (about 13 in 100) babies born alive with Edwards’ syndrome will live past their 1st birthday.
For more information on Edwards’ syndrome please access the NHS conditions website by clicking here. You can also speak to your community midwife or screening midwife for further support.
What is Patau’s syndrome?
A baby with Patau’s syndrome has 3 copies of chromosome number 13 instead of 2. This affects the way the baby grows and develops; this is a rare but serious condition. This usually happens by chance and is not caused by anything parents do before or during pregnancy. This syndrome severely disrupts normal development and, in many cases, results in miscarriage, stillbirth or the baby dying shortly after birth. Babies with Patau’s syndrome grow slowly in the womb and have a low birth weight, along with several serious medical problems. Babies with Patau’s syndrome can have a wide range of health problems.
For more information on Patau’s syndrome please access the NHS conditions website by clicking here. You can also speak to your community midwife or screening midwife for further support.
First trimester screening (Nuchal screening)
This screening test uses a blood test and an ultrasound scan to give you a high chance or a low chance result for Down’s syndrome, Edwards’ syndrome and Patau’s syndrome. This test can be performed from 11 – 14 weeks of pregnancy.
The ultrasound will measure the amount of fluid lying under the skin at the back of your baby’s neck. The results of your scan and blood test, along with your age, weight, stage of pregnancy and some other information (such as if you smoke), are put into a computer to work out the chance of your baby having one of these conditions. If you are having twins you will be offered the same tests as people only having one baby.
Second trimester screening
This screening test if offered if the sonographer is unable to measure the amount of fluid at the back of your baby’s neck at the dating scan. This can be due to the position baby is lying in, your BMI, being too early or too late in your pregnancy. This test can be offered from 14 weeks of pregnancy by your community midwife. For this screening test your midwife will take a blood test and this, combined with your age and your stage of pregnancy will give you a higher or lower chance of your baby having Down’s Syndrome. If you are having twins you will be offered the same tests as people only having one baby. However, it is important that you discuss this fully with your midwife or doctor before having this screening test as the detection rate can vary depending on what kind of twin pregnancy you have.
Results
If the screening test shows the chance of your baby having these three conditions are low, you will not be offered diagnostic testing. This does not mean that there is no chance the baby has these conditions, just that it’s unlikely. If the screening test shows that your baby has a higher chance, you will be contacted by the pregnancy screening midwife who will discuss the results with you and answer any questions you may have. The higher chance result usually means that there is a greater chance than 1 in 150 that your baby has one of these three conditions. You will be offered further screening to give a better indication of chance or a diagnostic test to confirm whether your baby has one of these three conditions.
As with all tests, you can choose whether or not to have the diagnostic tests.
PAPP-A
What is PAPP-A?
Pregnancy Associated Plasma Protein-A (PAPP-A) is a hormone that is made by the placenta (afterbirth) in pregnancy. It is measured as part of the first trimester screening blood test.
What does Low PAPP-A mean?
Low levels of PAPP-A (when it is less than 0.4 MoM in pregnancy) may be associated with:
- A lower birth weight baby as your placenta may not work as well
- An increased chance of having an early birth
- Miscarriage in the second half of pregnancy
- An increased chance of developing pre-eclampsia
At every appointment with either your midwife or doctor, you will be offered to have your blood pressure measured and your urine checked for protein. You will also be offered regular ultrasound scans, from 28 weeks, in order to monitor your baby’s wellbeing by taking measurements of your baby’s growth, your baby’s placental blood flow and the amount of amniotic fluid around your baby. You should also remain aware of your baby’s movements and follow the advice your midwife will give you at your 16 week appointment.
Receiving the news that you have low PAPP-A levels may cause anxiety but please be assured that the majority of babies will have normal growth and the pregnancy will progress without problem.
What will happen now?
If you have had an anatomy scan at 20 weeks then a customised growth chart will have been added to your hand held records so the growth of your baby throughout pregnancy can be monitored. You will continue to see your community midwife for your routine appointments but they will not measure your abdomen if you are having regular scans to monitor your baby’s growth and wellbeing.
If there are no concerns about the baby’s growth, then scans will be offered at 28, 34 and 39 weeks of pregnancy. However if there are any concerns about the baby’s growth or well-being, your scan will be reviewed and a plan put in place.
What can I do to help?
If you smoke, it is important that you stop smoking as smoking can affect the function of your placenta and reduce your baby’s growth. Your midwife can refer you to the smoking cessation programme.
Who can I speak with if I need further information?
You can speak to the pregnancy screening midwife, your midwife at your 16 week appointment or your consultant after your anatomy scan if you have further questions.
AFP
Why is AFP measured?
Alfa Fetal Protein (AFP) is a protein that is measured from your blood in the second trimester screening test. This, in combination with 3 other hormones, helps give you a screening result for Down’s Syndrome.
What does a high AFP mean?
The majority of babies are normal, however a very high AFP can be associated with Spina Bifida or anencephaly (conditions called Neural Tube Defects – NTD’s).
What happens if my test is positive?
You will have a detailed scan to look at the baby’s head and spine.
I have a high AFP. Can I still have a normal baby?
Yes. There can be several reasons for raised AFP in the mothers blood. These can be:
- You have been given the wrong due date
- You are carrying twins
- You have had bleeding in early pregnancy
- Sometimes there is no apparent cause for raised AFP.