Non‐invasive prenatal testing: clinical utility and ethical concerns about recent advances

To the Editor: Thomas and colleagues1 describe the ethical complexities that can arise in the use of non‐invasive prenatal testing (NIPT) based on the detection of cell‐free fetal DNA in the maternal circulation to screen for chromosomal and other genetic fetal conditions, especially if the clinical utility and implications of the testing are not well understood and explained. They indicate that “the current NIPT tests available are for specific chromosomal aneuploidy, extended panels of targeted conditions and low resolution whole genome sequencing”.

We support that all tests (for screening or diagnosis, and not just genetic tests) should be explained. However, we remind readers that there are specific tests using NIPT of cell‐free fetal DNA that have strong potential to benefit women and their fetuses and are at very low risk of the ethical hazards that concern Thomas and colleagues. A lead example is testing in women who are RhD (antigen) negative to predict whether the fetus is RHD (genotype) positive. Such testing can establish with a high level of certainty whether the fetus is RHD negative, in which case the woman can be spared the need for antenatal RhD immunoprophylaxis to prevent alloimmunisation. This approach not only spares around a third of women who are RhD‐negative the need for immunoprophylaxis but may also help reduce the burden on a small and altruistic pool of RhD immunoglobulin donors.2,3 In RhD‐negative women with preformed RhD antibodies, similar testing can be used to determine whether or not there is a need for intensive surveillance during the pregnancy for haemolytic disease of the fetus and newborn.

To consider all tests that use NIPT based on cell‐free fetal DNA as carrying the same complexity of explanation and ethical risk would resemble a conclusion that all immunochemistry is ethically risky because of the difficulties of explaining and interpreting prostate‐specific antigen tests, or that all fetal ultrasound is unethical because in some countries it is used inappropriately for sex selection. We encourage readers to consider that the underlying reason and specific target for each test, much more than the platform on which it is run, determines the level of ethical complexity.