The British Parliament has recently approved regulations to allow techniques ‘to prevent the transmission of serious mitochondrial disease from a mother to her child’. The regulations term these techniques ‘mitochondrial donation’, but in the popular media, the issue has been discussed under the heading of ‘three parent’ babies or ‘three parent’ embryos. This paper examines the language of the debate, with particular reference to one of the techniques approved. It concludes that the terminology of ‘mitochondrial donation’ is scientifically inaccurate and (...) ethically misleading, while the popular media description of ‘three parent’ embryos is broadly accurate, at least for one technique. This latter phrase also has the great merit, from an ethical perspective, of drawing attention to the ‘other woman’, the egg donor. She takes risks with her health in order to provide the egg which supplies the body of the embryo. Without her, this embryo simply would not exist. (shrink)