Purpose or Case Report: 1. Provide an overview of the science, indications and spectrum of noninvasive prenatal testing
2. Define the timing, accuracy and limitations of noninvasive prenatal testing
3. Describe the relationship and timing between noninvasive prenatal testing (Cell-free DNA screening), invasive prenatal testing (amniocentesis and chorionic villous sampling), and fetal imaging screening (nuchal translucency, fetal anatomic survey)
4. Summarize the impact of noninvasive prenatal testing on prenatal screening, testing and counseling
5. Discuss case reports that highlight the impact of NIPT on maternal-fetal management including fetal imaging
Methods & Materials: The science and methodology of noninvasive prenatal testing will be summarized from a review of scientific literature and current industry practices. The consensus statements and recommendations regarding NIPT from key medical societies including the American Congress of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine, and the National Society of Genetic Counselors will be reviewed and summarized. The maternal-fetal imaging indications and pathways for screen positive NIPT patients will be discussed from the perspective of an academic, tertiary care perinatal diagnostic center. This discussion will include real-life case reports and imaging from patients that are screen positive for aneuploidy and other genetic syndromes.
Results: Given the performance of conventional screening methods, the limitations of NIPT screening performance, and the limited data on cost-effectiveness in the low-risk obstetric population, conventional screening methods remain the most appropriate choice for first-line screening for most women in the general obstetric population.The patient choosing NIPT should understand the limitations and benefits of this screening in the context of alternative screening and diagnostic options. Given the potential for inaccurate results, a diagnostic test should be recommended for a patient who has a positive cell-free DNA test result.
Conclusions: Noninvasive prenatal testing has redefined the practice of prenatal genetic screening. Information obtained from NIPT has significant implications in prenatal and postnatal management including extent and frequency of prenatal imaging. It is incumbent on all fetal imagng professionals including radiologists to understand the information obtained with NIPT to appropriately counsel patients and coordinate prenatal care with the patient's provider.