Update on antenatal tests for Down’s syndrome
In a news item on 23 April 2015 we reported the results of a large international evaluation of non-invasive prenatal testing (NIPT) of mother’s blood in early pregnancy to diagnose Down’s syndrome. It was shown to be more accurate than the first trimester combined screen and had a much lower false positive rate. Mother’s with a positive screen are offered an invasive test, either amniocentesis or chorionic villus sampling, to make a firm diagnosis. Such tests carry about a 1% risk of miscarriage and a small risk of infection.
On 1 February 2016 we reported the news that the UK National Screening Committee had recommended that, because of its lower false positive rate, NIPT should be introduced into the NHS to be offered to women with high risk results from current screening tests so as to reduce the number of potential miscarriages following invasive diagnostic testing. The Department of Health has now approved the test. It is expected to be rolled out over the next three years.
Lyn Chitty, Professor of Genetics and Foetal Medicine at the Institute of Child Health, University College London, said "The staged roll-out will be important in allowing us to train all health professionals involved in delivering this new service to ensure parents have as much information as possible upon which to base decisions about their pregnancy, and to support them in those decisions."