Population and test characteristics of non-invasive prenatal testing (NIPT) during the evaluative rollout in England as part of a national screening programme

Introduction Non-invasive prenatal testing (NIPT) for Down’s syndrome, Edwards’ syndrome and Patau’s syndrome has become increasingly well established within antenatal screening worldwide. Within England, the evaluative rollout of NIPT began as part of the National Health Service (NHS) Fetal Anomaly Screening Programme pathway in June 2021 and ran until March 2024. NIPT is offered to all pregnant women with a higher chance result (≥1 in 150) from an NHS combined or NHS quadruple test. Methods The National Congenital Condition and Rare Disease Registration Service linked data from first-line NHS screening tests to NIPT tests across all laboratories in England. These linked data were used to describe (1) the eligible population and the proportion that had the test and (2) test characteristics including result status, turnaround times and proportion that were higher chance. Results During the rollout, the total number of singleton pregnancies with a higher chance first-line screen was 43 214 of which a majority (70.3%, n=30 367) had NIPT. Of those having NIPT, 98.5% received a reportable result and 87.2% of samples were reported to the maternity service within 5 days of being received in the laboratory. Of the pregnancies with a processed NIPT test, 7.3% had a higher chance NIPT result for at least one trisomy. Conclusions This evaluative rollout approach, particularly monitoring of test characteristics, allowed for adjustment of service delivery in real time. Linkage and integration of laboratory data is a compelling approach in monitoring aspects of performance of a screening test in a real-world setting.