Anyone who has spent more than a few years in medicine will be able to reflect on how views of what is or is not ethical have changed over time. Some actions are so clearly wrong that they are universally condemned but there are others over which reasonable people can and do disagree. It may be impossible to reach a consensus, so how should we proceed?

The National Screening Committee of the Department of Health is in the process of developing national standards for antenatal screening for Down’s syndrome. It is proposed to extend the offer of screening to all women and to define acceptable false-positive rates, …