The clinical usefulness of cell-free DNA screening in pregnancies with a
nuchal translucency between 95th and 99th percentile
Abstract
Objective: Evaluate the clinical usefulness of cell-free DNA screening
(cfDNA screening) in pregnancies with nuchal translucency (NT) between
95th and 99th percentile. Design: Subgroup analysis of a multicenter
prospective cohort study Setting: 12 different secondary and tertiary
health care institutions in Korea Sample: 7,547 singleton pregnant women
with NT between 95th and 99th percentile Methods: All participants were
provided with information about aneuploidy screening or diagnostic
testing and selected the first tier test after NT assessment. The first
tier test included maternal serum screening tests (MSS), cfDNA screening
and invasive test (IT). Main outcome measures: First-tier test
preference and chromosomal abnormalities in pregnancies with NT between
95th and 99th percentile Results: A total of 7,547 singleton pregnant
women were enrolled and 6,717 cases with known pregnancy outcomes were
analyzed. Among these, 89 (1.3%) cases showed NT between 95th and 99th
percentile. As the first-tier test, 47 (52.8%) cases chose cfDNA
screening, 33 (37.1%) cases selected IT, and nine (10.1%) cases
underwent MSS. Chromosomal abnormalities were found in five cases
(5.6%), including four cases with trisomy 21 (T21) and one with a
balanced translocation. No significant chromosomal abnormalities
undetected by cfDNA screening were noted in pregnancies with NT between
95th and 99th percentile. Conclusion: cfDNA screening in pregnancies
with NT between 95th and 99th percentile may be considered as an
acceptable alternative to invasive test for women intending to avoid the
risk of miscarriage.