It was a relief last month when the European Commission decided not to modify legislation on research involving the destruction of human embryos in response to a petition by the One of Us pro-life group. Even so, it is time to put a stop to this 'democracy carousel' (see Nature 508, 287; 2014).

Such citizen campaigns against embryo destruction disregard the births of more than 5 million babies as a result of advances in reproductive medicine. Moreover, selective abortion following an adverse genetic diagnosis can often be avoided, owing to advances in screening embryos before implantation. And embryonic stem-cell research is opening up regenerative medicine, which may eventually provide therapies for conditions such as pancreatic failure and age-related macular degeneration.

Central to the debate is the ethical status of the human embryo between fertilization and implantation. Many believe that, although a zygote has the potential to develop into a person, it is not yet a person. On this basis, destruction of donated embryos for medical research can be justified provided the work is subject to strict regulation and supervision. Indeed, a recent (unpublished) study shows that donation of spare embryos is widely supported by couples undergoing in vitro fertilization in Europe.