A new study suggests a DNA test for Down's syndrome on the National Health Service for pregnant women. According to researchers, the test can save the lives of unborn babies and reduce the need for invasive testing.
The research was conducted by the team of Professor Kypros Nicolaides at King's College Hospital and King's College London.
In the study, of those women judged to be at high risk for carrying a baby with Down's syndrome, about 60% of women chose the cell-free DNA test, compared to 38% opting for invasive testing.
At present, a woman's risk of carrying a baby with Down's syndrome is based on an assessment of her age, the level of hormones in her blood and the results of a 'nuchal scan.
Women deemed to be high risk following this 'combined assessment' are given the option of further tests. CVS or amniocentesis are still the only examinations that can provide a definitive diagnosis of Down's syndrome, but carry a risk of miscarriage.
The study involved 11,692 women with single pregnancies. A small proportion of these women (395) were found to be at high-risk for Down's syndrome.
The cell-free DNA test is a highly reliable test for Down's syndrome, but is currently only available privately and costs hundreds of pounds.
The results suggest that the best approach to screening for Down's syndrome is to offer the combined test to all pregnant women and, based on the results of the test, to select a group that would benefit from the cell-free DNA test.