Mitra Anjali N, Dingel Aleksei, Kolarova Teodora, MacKinnon Hayley J, Katz Ronit, Lockwood Christina M, Shree Raj
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington.
School of Medicine, University of Washington, Seattle, Washington.
Am J Perinatol. 2025 Jan;42(1):6-13. doi: 10.1055/s-0044-1789573. Epub 2024 Aug 29.
Low fetal fraction (FF) on cell-free DNA (cfDNA)-based noninvasive prenatal screening (NIPS) is a common etiology for indeterminate results. As maternal Black race is implicated as a risk factor for low FF and more indeterminate results, we sought to evaluate this association.
This was a single-institution, retrospective cohort study of cfDNA-based NIPS performed between May 2017 and May 2022 with complete clinical data abstraction. We compared FF, indeterminate rates, and total cfDNA concentration among self-reported Black, White, and Other groups from NIPS results from 2017 to 2022 with full clinical data abstraction. Using linear regression and interaction testing, we evaluated associations between self-reported race, FF, indeterminate rate, and total cfDNA concentration.
In total, 1,591 participants met the inclusion criteria; 70.8% ( = 1,126) self-identified as White, 6.9% ( = 110) as Black, and 22.3% ( = 355) self-identified with another race. Mean FF was not different between the White, Black, or Other groups (11.8 vs. 11.2 vs. 11.7%, respectively, = 0.52). This remained true after adjusting for body mass index (BMI), gestational age (GA) at draw, and fetal sex (all > 0.17). Interaction testing for FF and total cfDNA by race with BMI, GA at draw, and fetal sex demonstrated no effect modification.
In our population, maternal self-identified race, particularly Black race, does not affect FF. Biological plausibility for race-based differences on clinical tests requires ongoing thoughtful consideration.
· NIPS is widely used to screen for fetal aneuploidy.. · FF is an important test metric, and low FF is associated with adverse outcomes, like aneuploidy.. · In existing studies, Black race is implicated as a risk factor for lower FF.. · Our study found no differences in FF between groups by self-reported race.. · Biological plausibility for race-based differences on clinical tests requires ongoing consideration..
基于游离 DNA（cfDNA）的无创产前筛查（NIPS）中胎儿游离 DNA 比例（FF）低是结果不确定的常见原因。由于孕妇黑人种族被认为是 FF 低和更多结果不确定的风险因素，我们试图评估这种关联。
这是一项单机构回顾性队列研究，研究对象为 2017 年 5 月至 2022 年 5 月期间进行的基于 cfDNA 的 NIPS，且有完整的临床数据提取。我们比较了 2017 年至 2022 年 NIPS 结果中自我报告为黑人、白人及其他种族组之间的 FF、不确定率和总 cfDNA 浓度，并进行了完整的临床数据提取。使用线性回归和交互作用检验，我们评估了自我报告的种族、FF、不确定率和总 cfDNA 浓度之间的关联。
共有 1591 名参与者符合纳入标准；70.8%（n = 1126）自我认定为白人，6.9%（n = 110）为黑人，22.3%（n = 355）自我认定为其他种族。白人、黑人或其他种族组之间的平均 FF 无差异（分别为 11.8%、11.2%和 11.7%，P = 0.52）。在调整体重指数（BMI）、采血时的孕周（GA）和胎儿性别后，情况依然如此（所有 P > 0.17）。按种族对 FF 和总 cfDNA 与 BMI、采血时的 GA 和胎儿性别进行交互作用检验，未显示有效应修饰。
在我们的研究人群中，孕妇自我认定的种族，尤其是黑人种族，不会影响 FF。对于临床检测中基于种族的差异，其生物学合理性需要持续深入思考。
· NIPS 被广泛用于筛查胎儿非整倍体。· FF 是一项重要的检测指标，FF 低与非整倍体等不良结局相关。· 在现有研究中，黑人种族被认为是 FF 较低的风险因素。· 我们的研究发现，自我报告的种族组之间 FF 无差异。· 对于临床检测中基于种族的差异，其生物学合理性需要持续考量。
