Accurate test, potential to reduce unnecessary Tx
Fetal RhD testing at 27 weeks’ gestation appears to be highly accurate and could reduce the unnecessary use of anti-D immunoglobulin when the fetal RhD is negative.
Different results by ethnicity?
Dutch participants are not necessarily reflective of the US population. Known variation in the rate of fetal RhD positivity among RhD-negative pregnant women by race and ethnicity could mean that the number of women able to forego anti-D immunoglobulin prophylaxis would be different in the United States than in other countries.
Also, in this study, polymerase chain reaction for two RhD sequences was run in triplicate, and a computer-based algorithm was used to automatically score samples to provide results. For safe implementation, the cell-free fetal RhD DNA testing process would need to follow similar methods.
CHALLENGES TO IMPLEMENTATION
Cost and availability are big unknowns
Cost and availability of the test may be barriers, but there is currently too little information on either subject in the United States to make a determination. A 2013 study indicated that the use of cell-free DNA testing to determine fetal RhD status was then approximately $682.10
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center for Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health.
Copyright © 2018. The Family Physicians Inquiries Network. All rights reserved.
Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2018;67: 306, 308, 319).