A need for definition: a matter of life and death for human embryos

A recent IMJ commentaryon brain stem death criteria summarised ethical and technical issues concerning “end of life decisions”, and we concur that physicians should have competence in eliciting the proper sequence of brain stem signs in clinical practice. However, a truly comprehensive dialogue on the definition of death should address another question that confronts IVF clinics in Ireland each day—when does a human embryo die? Despite the enormous social and political energy focused on “right to life” issues over recent decades, the death of a human embryo remains a sadly forgotten topic. As Dr Murphy indicated1, the introduction of brain stem death criteria in 1967 recognised permanent loss of consciousness and spontaneous breathing after the inactivation of essential human neural elements. But our IVF clinics and allied research facilities are responsible for human life well before any discrete neurological system has developed. For practitioners and scientists engaged in the care of these tiniest of “patients”, a relevant definition of death should not be neglected.