To place in context the decisional support needs women and their partners may have that are specific to cfDNA NIPT, it is helpful to first describe the pre-cfDNA NIPT screening landscape. Prior to the introduction of commercial cfDNA NIPT in…
Cell-Free DNA-Based Prenatal Testing as a Genetic Test in Laboratories Cell-free DNA-based prenatal testing is a screening test that estimates the risk of fetal aneuploidy (trisomy 21, 18, and 13) by analyzing cell-free DNA (cfDNA) circulating in the maternal plasma…
Introduction External Quality Assessment (EQA), which is also referred to as proficiency testing (PT) in some countries, is a means of assessing clinical analytical and interpretation performance with interlaboratory comparison and against international standards (ISO). EQA allows an independent appraisal…
Introduction Extracellular nucleic acids have already been known to exist in the blood circulation since 1948 . The observation of abnormally high concentrations of DNA in serum of cancer patients lead Stroun et al. to suggest that DNA found in…
Introduction The groundbreaking discovery of the presence of cell-free DNA in maternal plasma was made in 1997 by Dennis Lo . In the years since that, gradual technological development has meant that we can now use a maternal plasma sample…
Hemolytic Disease of the Fetus and Newborn Hemolytic disease of the fetus and newborn (HDFN) is a disease caused by maternal IgG alloantibodies against paternally inherited RBC alloantigens, for which the maternal cells are negative. The maternal alloantibodies are induced…
Acknowledgments I am indebted to my clinical laboratory and analytical teams and thank them for their support—Nicola Flowers, Olivia Giouzeppos, Grace Shi, Clare Love, Rebecca Manser, Ian Burns, Shelley Baeffel, Sera Tsegay, Tom Harrington, and LaiEs Carver. Research conducted at…
Introduction Due to an increasing trend of advancing maternal age at conception, and the increased use of assisted reproductive technologies (ART), the number of twin and higher order multiple pregnancies is increasing in many countries, despite the introduction of the…
Introduction Since the commercial introduction of cfDNA-based prenatal tests in 2011, a plethora of studies with designs of proof of concept, validation, case reports, large cohort studies, and meta-analyses have been published. Although cfDNA-based prenatal screening for trisomy 21, 18,…
Prenatal Screening Before Cell-Free DNA-Based NIPT Aneuploidies Aneuploidies, the presence of an abnormal number of chromosomes, are conditions associated with significant morbidity and mortality. Aneuploidies affect approximately 1 in 160 live births , although the overall incidence is higher due…