Non-invasive prenatal testing (NIPT) is increasingly being adopted as a screening test in the UK and is currently accessed through certain National Health Service healthcare systems or by private provision. This audit aims to describe reasons for and results of cytogenomic investigations carried out within UK genetic laboratories following an NIPT result indicating increased chance of cytogenomic abnormality (‘high-chance NIPT result’).

A questionnaire was sent out to 24 genetics laboratories in the UK and completed by 18/24 (75%).

Data were returned representing 1831 singleton pregnancies. A total of 1329 (73%) invasive samples were taken following NIPT results showing a high chance of trisomy 21; this was confirmed in 1305 (98%) of these by invasive sampling. Trisomy 21 was confirmed in >99% of patients who also had high-screen risk results or abnormal scan findings. Amongst invasive samples taken due to NIPT results indicating a high chance of trisomy 18, 84% yielded a compatible result, and this number dropped to 49% for trisomy 13 and 51% for sex chromosomes.

In the UK, the majority of patients having invasive sampling for high-chance NIPT results are doing so following an NIPT result indicating an increased chance of common trisomies (92%). In this population, NIPT performs particularly well for trisomy 21, but less well for other indications.

在英国，无创产前检查（NIPT）越来越多地被用作筛查测试，目前可通过某些国家卫生服务系统或私人机构使用。该审核旨在描述在NIPT结果表明细胞基因组异常机会增加（“ NIPT高结果”）之后，英国基因实验室进行细胞基因组研究的原因和结果。

问卷已发送至英国的24个遗传学实验室，并于18/24（75％）时完成。

返回的数据表示1831单身孕妇。NIPT结果后共采集了1329个（73％）浸润性样品，显示21三体性的机会很高；在1305（98％）的侵入性采样中证实了这一点。在> 99％的患者中，也有高筛查风险结果或异常扫描结果被确认为21三体。在由于NIPT结果而获得的侵入性样本中，表明18三体性的可能性很高，其中84％产生了相符的结果，对于13三体性，该数字下降到49％，对于性染色体，这一数字下降到51％。

在英国，大多数采取有创采样以获取高可能性NIPT结果的患者是在NIPT结果表明出现普通三体症的机会增加后才这样做的（92％）。在该人群中，NIPT在21三体性疾病中表现尤其出色，但在其他适应症中表现不佳。