Clinical impact of additional findings detected by genome-wide non-invasive prenatal testing: Follow-up results of the TRIDENT-2 study

[published correction appears in Am J Hum Genet. 2022 Jul 7;109(7):1344]. van Prooyen Schuurman L, Sistermans EA, Van Opstal D, et al. Am J Hum Genet. 2022;109(6):1140-1152. doi:10.1016/j.ajhg.2022.04.018. Open Access: Learn more

Tags: Clinical Experience / Clinical Utility, 2022, Netherlands, RAAs, CNVs

  • “Between April 2017 and April 2019, additional findings were detected in 402/110,739 pregnancies (0.36%). For 358 cases, the origin was proven to be either fetal (n = 79; 22.1%), (assumed) confined placental mosaicism (CPM) (n = 189; 52.8%), or maternal (n = 90; 25.1%). For the remaining 44 (10.9%), the origin of the aberration could not be determined. Most fetal chromosomal aberrations were pathogenic and associated with severe clinical phenotypes (61/79; 77.2%). For CPM cases, occurrence of pre-eclampsia (8.5% [16/189] vs 0.5% [754/159,924]; RR 18.5), and birth weight <2.3rd percentile (13.6% [24/177] vs 2.5% [3,892/155,491]; RR 5.5) were significantly increased compared to the general obstetric population. Of the 90 maternal findings, 12 (13.3%) were malignancies and 32 (35.6%) (mosaic) pathogenic copy number variants, mostly associated with mild or no clinical phenotypes.”
  • “In conclusion, about one in every 275 women in a general obstetric population opting for GW-NIPT receives an additional finding. The majority of additional findings identified by GW-NIPT have clinical impact. Most fetal chromosomal aberrations are pathogenic and associated with severe clinical phenotypes. (Assumed) CPM is significantly associated with adverse perinatal outcomes, requiring tailored obstetric care.”