Key clinical point: In women at low risk for aneuploidy, single-nucleotide polymorphism-based cell-free DNA (cfDNA) screening for trisomies 21, 18, and 13 (T21, T18, T13, respectively) demonstrates similar high sensitivity, specificity, and positive predictive value (PPV) as those in high-risk women.
Main finding: In low-risk vs. high-risk women, T21 was detected with similar sensitivity (100% vs. 98.8%; P = 1.0), specificity (99.98% vs. 99.96%; P = .61), and a high PPV (85.71% vs. 97.53%; P = .06), with analogous results for T18 and T13.
Study details: Findings are from a multicenter, prospective, observational SMART study including 17,851 pregnant women undergoing cfDNA screening for aneuploidy and 22q11.2DS, along with DNA analysis of the fetus or newborn. Of these, 13,043 pregnancies were at low risk for aneuploidy, with the rest being high risk.
Disclosures: The study was funded by Natera, Inc, CA, USA. Some of the authors, including the lead author, received institutional research support from Natera. M Egbert, Z Demko, M Rabinowitz, and K Martin serve as an employee/consultant of Natera and own stocks/options. J Hyett has participated in expert consultancies for and B Jacobson reports research clinical diagnostic trials with Natera, among others.
Source: Dar P et al. Am J Obstet Gynecol. 2022 (Jan 24). Doi: 10.1016/j.ajog.2022.01.019.