You’ll be offered screening to find out how likely it is that your baby may have Down’s syndrome, Edwards’ syndrome, or Patau’s syndrome.
In the UK:
- around 1 baby in every 700 births has Down’s syndrome - it’s the most common chromosomal condition
- around 1 baby in every 5000 births has Edwards’ syndrome - it’s the second most common chromosomal condition
- around 1 baby in every 16,000 births has Patau’s syndrome
Choosing which to be screened for
During the first trimester you can choose to be screened to find out if your baby may have:
- Down’s syndrome only
- Edwards’ syndrome and Patau’s syndrome only
- all 3 conditions
You can choose not to have any of these screening tests if you don't want them.
Pregnancies with more than one baby
You’ll be offered the same screening choices if you’re pregnant with twins as you would be if you were pregnant with one baby.
Screening tests may be less accurate with twin pregnancies.
Your midwife will help you to understand what this means and support you to decide if choosing further tests feels right for you and your babies.
NIPT is not suitable for triplet pregnancies, or pregnancies with more than 3 babies.
Our bodies are made from millions of cells, and inside every cell there are chromosomes. Chromosomes carry genes that determine how we develop.
People usually have 46 chromosomes, 23 from the mother and 23 from the father. If babies have an extra full or partial chromosome in their cells, they’ll have a chromosomal condition. If this is only in some of their cells, it may be called mosaicism.
Down’s syndrome, Edwards’ syndrome and Patau’s syndrome are separate conditions. Most forms of chromosomal conditions happen by chance. They’re not caused by anything parents do before or during pregnancy.
Older mothers are more likely to have a baby with one of the conditions and the chance increases with the mother’s age at pregnancy. But Down’s syndrome, Edwards’ syndrome and Patau’s syndrome can occur in pregnancy for women of any age.
All pregnant women, no matter what age, can have the test.
Read more about Down’s syndrome
Read more about Edwards’ syndrome
Read more about Patau’s syndrome