ISUOG consensus statement on the impact of non-invasive prenatal testing (NIPT) on prenatal ultrasound practice

The emergence of effective cell-free fetal DNA-based techniques to screen for trisomy 21 and other aneuploidies has greatly expanded the range of prenatal tests available over the last few years. Non-invasive prenatal testing (NIPT) is rapidly being incorporated into prenatal care, thus changing the traditional approach to prenatal screening and diagnosis. However, although NIPT techniques are highly efficient, their role and performance must be considered alongside and combined with other screening modalities. The role of prenatal ultrasound in particular needs to be reassessed as NIPT becomes more widely available. It is important to emphasize that the main goal of prenatal screening is to provide accurate information that will facilitate the delivery of optimized antenatal care, with the best possible outcome for both mother and fetus. Women should be informed about prenatal screening performance by appropriately trained health professionals, allowing them to make an informed decision. It is the parent's choice to undergo such procedures, and their wishes should be determined and respected. Screening strategies based on individual risk calculated from maternal age and nuchal translucency measurement and/or maternal serum markers and/or other ultrasound markers in the first trimester (defined by the conventional crown–rump length range of 45–84 mm). At the moment, ISUOG endorses this strategy. Following such screening, women can be offered a choice, according to their calculated individual risk, of having no further testing, undergoing NIPT, or undergoing invasive testing. Cut-offs should be defined on a local/national basis and will be affected by public health priorities and available resources. Invasive testing based on background risk (including, for example, maternal age and history of aneuploidy), with no other individual risk calculation. NIPT as a first-line screening test. Most current guidelines endorse NIPT only for high-risk populations for which adequate data exist. Using NIPT on intermediate- or low-risk patients might be endorsed as a widely available option only when new data emerge and NIPT costs decrease.