biostudies-literatureKolarova TRNational Center for Advancing Translational SciencesNCATS NIH HHSNHLBI Division of Intramural ResearchNHLBI NIH HHSNIGMS NIH HHS456-458https://www.ebi.ac.uk/biostudies/studies/S-EPMC10922755biostudies-literatureUnknown143(3)Uterine leiomyomas may affect the performance of cell-free DNA (cfDNA)-based noninvasive prenatal testing (NIPT). We conducted a retrospective cohort study of pregnant individuals with and without leiomyomas undergoing first-trimester cfDNA-based NIPT. Characteristics of NIPT in patients with leiomyomas (n=122) were compared with those in patients without leiomyomas (n=937). Mean fetal fraction was lower in patients with leiomyomas compared with patients without (10.0% vs 11.5%; P =.001); however, the rate of indeterminate results was different only in patients without obesity (body mass index [BMI] lower than 30) (5.3% vs 1.5%; P =0.03). Total cfDNA concentration was higher in patients with leiomyomas ( P =.002), suggesting possible dilution of the fetal fraction. Leiomyoma size did not affect NIPT metrics. In conclusion, uterine leiomyomas are associated with lower fetal fraction and, in patients without obesity, with a higher rate of indeterminate results independent of leiomyoma size.Obstetrics and gynecologyEffect of Uterine Leiomyomas on Noninvasive Prenatal Testing Parameters in the First Trimester.PMC10922755K08 HL150169K08HL150169T32 GM007454UL1 TR002319Buchan JGLockwood CMacKinnon HChen LKolarova TRShree RAlderson AfalseEffect of Uterine Leiomyomas on Noninvasive Prenatal Testing Parameters in the First Trimester.Uterine leiomyomas may affect the performance of cell-free DNA (cfDNA)-based noninvasive prenatal testing (NIPT). We conducted a retrospective cohort study of pregnant individuals with and without leiomyomas undergoing first-trimester cfDNA-based NIPT. Characteristics of NIPT in patients with leiomyomas (n=122) were compared with those in patients without leiomyomas (n=937). Mean fetal fraction was lower in patients with leiomyomas compared with patients without (10.0% vs 11.5%; P =.001); however, the rate of indeterminate results was different only in patients without obesity (body mass index [BMI] lower than 30) (5.3% vs 1.5%; P =0.03). Total cfDNA concentration was higher in patients with leiomyomas ( P =.002), suggesting possible dilution of the fetal fraction. Leiomyoma size did not affect NIPT metrics. In conclusion, uterine leiomyomas are associated with lower fetal fraction and, in patients without obesity, with a higher rate of indeterminate results independent of leiomyoma size.2024-01-01T00:00:00Z2024 Mar2025-04-04T19:26:25.538Z2025-04-04T19:26:25.538ZS-EPMC109227553820733810.1097/aog.000000000000550410.1097/AOG.0000000000005504