Numbers of prenatal cell‐free DNA screens performed: Results of a 2022 CAP exercise

Objective Determine current analytical methods and number of cell‐free (cf) DNA prenatal screening tests performed for common trisomies. Methods The College of American Pathologists 2022‐B Noninvasive Prenatal Testing exercise was distributed in December 2022 to 93 participants in 22 countries. Supplemental questions included the number of tests performed in a recent month and the proportion of samples originating outside the United States (US). Results Eighty‐three participants from three continents returned results; 74 (89%) were suitable for the analyses. Nine manufacturer/platform combinations were identified, most commonly Illumina/Nextseq (55%). The most common methodology was whole genome sequencing (76%). Annualized cfDNA tests were 2.80 million, with Asian, European and North American participants representing 10.6%, 6.5% and 82.9% of tests, respectively. When restricted to US in‐country tests, the annualized rate was 2.18 million, with four of 20 participants testing 79.2%. Among 73 respondents, 63 (86%) were for‐profit, eight (11%) were non‐profit academic or government supported and the remaining two included hospital‐based and private non‐profit. Eighteen (25%) supported relevant academic training. Conclusion In 2011, screening for common trisomies was based on serum/ultrasound markers with an estimated 2.96 million US pregnancies screened in 131 laboratories. In 2022, cfDNA‐based screening was offered by 20 laboratories testing 2.18 million US pregnancies. Key points What's already known about this topic? Serum/ultrasound based prenatal screening for common trisomies is being replaced by cell‐free (cf) DNA‐based screening for common trisomies. What does this study add? In 2022, an estimated 59% of all United States (US) pregnancies received cfDNA screening for common trisomies, with four of 20 reporting laboratories performing 79% of these tests.