Chitty and Kroese’s editorial on realising the promise of non-invasive prenatal testing (NIPT) based on cell-free DNA in maternal plasma reaffirms the concept of superior performance compared with conventional screening.1 However, the comparison was performed with standard first trimester screening and not with other screening methods that have higher sensitivity and specificity.2 The same team carried out a study in a cohort of 452 901 women, 74% of whom were under 35 years of age.3 Abnormal karyotypes were less likely to be identified with cell-free DNA than with sequential screening (75.4% v 81.6%). Overall, sequential screening has better test performance than cell-free DNA.4NIPT provides a good opportunity to change prenatal genetic testing, but the process must be closely monitored by the scientific community. Before cell-free DNA is adopted for primary population screening further clarification is needed, including whether this test is truly needed or whether we are creating artificial market needs, whether NIPT should be the standard screening test for all pregnant women, and “what to test for?”The scientific community should exercise careful control and not be overwhelmed by the progress.NotesCite this as: BMJ 2015;350:h2518