Trends in Invasive Prenatal Testing, Diagnosis, and Abortion for Fetal Aneuploidy

We aimed to assess trends in prenatal testing for aneuploidy, including indications, diagnostic yield, and the timing of diagnosis and abortions since the introduction of cell-free DNA (cfDNA) into routine prenatal care. In this observational retrospective study, all invasive prenatal diagnostic procedures performed at a single institution from 2010 to 2022 were evaluated. Clinical variables included gestational age (GA) at testing, indications, results, and pregnancy outcomes (continuation or abortion). Description statistics were used to characterize the sample. A total of 1,262 diagnostic procedures were performed during the study period, with 20.5% (n = 258) confirming genetic abnormalities. Amniocentesis accounted for 70.4% (n = 888) of diagnostic procedures, while 29.6% underwent chorionic villus sampling (CVS; n = 374). The number of procedures decreased significantly over time (p < 0.001). Indications for testing shifted dramatically; testing for the indication of advanced maternal age alone fell from 45 to 5.6% (p < 0.001). Patients with abnormal cfDNA screening results underwent diagnostic testing at an earlier average gestational age (15.3 vs. 17.8 weeks; p < 0.001), had a higher likelihood of undergoing CVS (30.7 vs. 8.9%; p < 0.001), and had higher rates of abnormal cytogenetics (60.4 vs. 13.2%; p < 0.001) compared to patients with analyte testing. Patients diagnosed with aneuploidy following abnormal cfDNA underwent abortion at earlier GA (15.5 vs.19.3 weeks; p = 0.002). cfDNA screening has reduced prenatal invasive diagnostic procedures and shifted testing indications. Abnormal cfDNA screening is associated with a higher diagnostic yield and earlier GA at diagnosis and abortion after confirmation of aneuploidy. Despite these advances, aneuploidy diagnosis continues to extend into the second trimester, highlighting ongoing challenges in early detection.