Objective: To determine expert consensus on which chromosomal abnormalities should and should not be detected in prenatal diagnosis, and for which abnormalities disagreement remains after structured discussion.
Methods: An expert panel of 24 prenatal experts (8 clinical cytogeneticists, 8 clinical geneticists and 8 obstetricians) rated 15 chromosomal abnormalities sampled from a nationwide study on rapid aneuploidy detection (RAD). In two individual anonymous rating rounds and one group meeting, the participants rated PRO or AGAINST detection and stated their main argument. The 15 chromosomal abnormalities were described in detail by a stylized vignette containing an obstetrical history, the indication for prenatal diagnosis and the range of possible outcomes of the chromosomal abnormality. Consensus was defined to be present if at least 80% of the experts agreed.
Results: Consensus was reached in 12 out of 15 cases. In ten cases, there was agreement PRO detection and in two cases experts agreed AGAINST detection. At the end of the third round, dissensus remained on three abnormalities.
Conclusion: Experts largely agreed on detecting chromosomal abnormalities with severe consequences and AGAINST detection in case of irrelevant clinical consequences. For chromosomal abnormalities with mild or uncertain outcomes, dissensus remained. None of the currently available tests corresponds to these demands.