During pregnancy, you can have screening tests to find out whether your unborn baby has a congenital disorder or any physical abnormalities. This is called prenatal screening. There are two screening tests:

  1. prenatal screening for Down syndrome, Edwards’ syndrome and Patau's syndrome, and
  2. screening for physical abnormalities (anomaly scan).

It’s entirely up to you to decide whether or not you want to take these screening tests.

Screening for Down’s, Edwards’ and Patau’s syndromes

If you decide to have your child tested for Down’s, Edwards’ and Patau’s syndromes, you can choose to have:

  • The NIPT (non-invasive prenatal testing). . The NIPT is a screening test in which a blood sample from a pregnant woman is tested. The blood sample is tested in a laboratory. If this screening test shows that the baby may have Down syndrome, Edwards’ syndrome or Patau’s syndrome, follow-up diagnostic testing is needed, just to be sure. You can have a NIPT from week 11 of your pregnancy.


  • The combined test: a blood test between the ninth and fourteenth week and an ultrasound scan between the eleventh and fourteenth week of pregnancy.

You can download leaflets about the screening for Down’s, Edwards’ and Patau’s syndromes in five languages.

Screening for physical abnormalities (anomaly scan)

The anomaly scan is a medical examination. Another name for it is the structural ultrasound scan. The aim is to find out whether the baby has any physical abnormalities. These include spina bifida (an open spine), anencephaly (where most of the brain and spinal cord is missing), hydrocephalus (water on the brain), heart defects, diaphragmatic hernia, abdominal hernia, either absent or abnormal kidneys, abnormal bone development, and abnormalities of the arms or legs. The sonographer also checks whether the baby is growing properly and whether there is sufficient amniotic fluid.

You can have an anomaly scan from week 18 to week 21 of your pregnancy (which is 21 weeks and 0 days into your pregnancy). It should ideally be in week 19 of your pregnancy (which is 19 weeks and 0 days to 19 weeks and 6 days into your pregnancy).
You can download  leaflets about the anomaly scan in five languages.

Diagnostic tests

Screening tests can tell you how likely it is that your baby may have a condition. Only a diagnostic test can tell you whether your baby actually has the condition.