Screening for Down's syndrome, Edwards' syndrome and Patau's syndrome

You will be offered a screening test for Down's syndrome, Edwards' syndrome and Patau's syndrome between 11 weeks and 13 weeks 6 days of pregnancy. This is to assess your chances of having a baby with one of these conditions.

Down's syndrome is also called trisomy 21 or T21. Edwards' syndrome is also called trisomy 18 or T18, and Patau's syndrome is also called trisomy 13 or T13.

If a screening test shows that you have a higher chance of having a baby with Down's syndrome, Edwards' syndrome or Patau's syndrome, you'll be offered further tests to find out for certain if your baby has the condition.

What are Down's syndrome, Edwards' syndrome and Patau's syndrome?

Down's syndrome, 21 trisomy, 3 cromosomes of the 21.

Down's syndrome causes some level of learning disability.

People with Down's syndrome may be more likely to have other health conditions, such as heart conditions, and problems with the digestive system, hearing and vision. Sometimes these can be serious, but many can be treated.

Edwards' syndrome and Patau's syndrome

Sadly, most babies with Edwards' syndrome or Patau's syndrome will die before or shortly after birth. Some babies may survive to adulthood, but this is rare.

All babies born with Edwards' syndrome or Patau's syndrome will have a wide range of problems, which can be very serious. These may include major complications affecting their brain.

What does screening for Down's syndrome, Edwards' syndrome and Patau's syndrome involve?

Combined test

A screening test for Down's syndrome, Edwards' syndrome and Patau's syndrome is available between weeks 11 weeks to 13 weeks 6 days of pregnancy. It's called the combined test because it combines an ultrasound scan with a blood test (BHCG and PAPP-A). The blood test can be carried out at the same time as the 12 weeks scan.