In the UK, all pregnant women are offered initial screening tests, from 10 weeks of pregnancy, referred to as “the combined test,” and if indicated, further diagnostic testing for Down syndrome. The combined test assesses the risk or likelihood of the fetus having a diagnosis of Down Syndrome. This uses maternal age, biochemical markers in the blood and ultrasound measurements.

An alternative “quadruple test” may be used to screen for Down Syndrome only between 14+2 and 20 weeks’ gestation. This may be offered if specific markers on fetal ultrasound cannot be obtained or if specific fetal measurements are identified.

Non-Invasive Prenatal Testing (NIPT), is a relatively new method of screening, this involves analysing cell-free maternal and fetal DNA in the mother’s blood, from 10 weeks of gestation. The sensitivity of testing for Down syndrome is reported to be 97.4%. However, there can be false negative, false positive and inconclusive results. NIPT Screening is now available on the NHS, and if offered to women whose results are in the higher risk category on the combined or quadruple tests for the fetus having a Down Syndrome diagnosis. This may be offered to mothers who have either singleton or twin pregnancies.

Currently, confirmatory diagnostic tests for Down syndrome involve an amniocentesis, this carries a small risk of a miscarriage.

Many parents wish to proceed for diagnostic testing to prepare themselves psychologically, at the time of their baby’s birth, rather than for the purpose of termination. It is important that professionals provide balanced, accurate, up to date information in a sensitive and non-judgmental manner; ensuring that the woman is supported by her partner at the time of imparting the news.

It is helpful to signpost parents to the local parents’ Down syndrome support group and the Down’s Syndrome Association to obtain further information.

Updated by Dr E Telford, August 2025.