Fetal Fraction and Noninvasive Prenatal Testing: What Clinicians Need to Know

Overview

Journal Prenat Diagn

Publisher Wiley

Specialty Gynecology & Obstetrics

Date 2019 Dec 11

PMID 31821597

Citations 45

Authors

Lisa Hui

Diana W Bianchi

Affiliations

Soon will be listed here.

Abstract

The fetal fraction (FF) is a function of both biological factors and bioinformatics algorithms used to interpret DNA sequencing results. It is an essential quality control component of noninvasive prenatal testing (NIPT) results. Clinicians need to understand the biological influences on FF to be able to provide optimal post-test counseling and clinical management. There are many different technologies available for the measurement of FF. Clinicians do not need to know the details behind the bioinformatics algorithms of FF measurements, but they do need to appreciate the significant variations between the different sequencing technologies used by different laboratories. There is no universal FF threshold that is applicable across all platforms and there have not been any differences demonstrated in NIPT performance by sequencing platform or method of FF calculation. Importantly, while FF should be routinely measured, there is not yet a consensus as to whether it should be routinely reported to the clinician. The clinician should know what to expect from a standard test report and whether reasons for failed NIPT results are revealed. Emerging solutions to the challenges of samples with low FF should reduce rates of failed NIPT in the future. In the meantime, having a "plan B" prepared for those patients for whom NIPT is unsuccessful is essential in today's clinical practice.

Citing Articles

Factors, pregnancy outcomes, and management associated with non-reportable results in prenatal cell-free DNA testing.

Yin H, Wang J, Wu X, Miao M, Wang Y, Shi J Arch Gynecol Obstet. 2025; .

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BinDel: Detecting Clinically Relevant Fetal Genomic Microdeletions Using Low-Coverage Whole-Genome Sequencing-Based NIPT.

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The association between the amount of fetal fraction in cell-free DNA testing and adverse pregnancy outcomes: A cohort study.

Aryavand M, Nurzadeh M, Ghaemi M, Eskandari Delfan S, Marsoosi V Int J Reprod Biomed. 2025; 22(11):919-926.

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Evaluation of the clinical utility of NIPT-plus and analysis of adverse pregnancy outcomes.

Zhang L, Chang B, Wang L, Mijiti G, Bahetibieke K, Xue S Arch Gynecol Obstet. 2024; 310(6):2973-2981.

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Early Non-Invasive Prenatal Testing at 6-9 Weeks of Gestation.

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