The Vatican newspaper has re-opened the debate over whether brain death — defined as the cessation of all brain functions — marks the definitive end of life, as opposed to the moment when the heart stops beating.

In a front page article in L'Osservatore Romano, Lucetta Scaraffia, Professor of Modern History at a Rome university and a regular contributor to the newspaper and the Italian media, noted that the Vatican had adopted brain death as a criterion for declaring a person dead after the publication of a landmark report by Harvard Medical School 40 years ago.

Professor Scaraffia said that in 1985, and again in 1989 and 2006, the Pontifical Academy of Sciences had recognised brain death as "the true criterion for death". The 2006 document, entitled Why the Concept of Brain Death Is Valid as a Definition of Death, was signed by Cardinal Georges Cottier, then theologian to the papal household; Cardinal Alfonso Lopez Trujillo, at the time president of the Pontifical Council for the Family; Cardinal Carlo Maria Martini, the former Archbishop of Milan; and Bishop Elio Sgreccia, the then president of the Pontifical Academy for Life.

The Vatican had thus accepted that the cessation of heart and lung functions was no longer the only criterion for declaring someone dead, Professor Scaraffia said. However it was time this was re-examined, since members of the Roman Catholic Church in practice had voiced "many reservations", and in Vatican City itself "the certification of brain death is not used".

Professor Scaraffia, who is vice-president of the Italian Association for Science and Life and a member of the Italian National Committee on Bio-Ethics, said that acceptance of brain death raised a range of ethical issues such as the transplanting of organs from a person whose brain had ceased but whose bodily functions continued because of a respirator.

She noted that in 1991 Cardinal Joseph Ratzinger, then head of the Congregation for the Doctrine of the Faith and now Pope Benedict XVI, had drawn attention to the danger that people who fell into an "irreversible coma" because of illness or an accident might have their organs used for transplants or experiments.

Profesor Scaraffia said that there had even been at least one case in which life support machines were used on a brain-dead pregnant woman to ensure that her blood kept circulating and her lungs continued to produce oxygen until the baby was delivered.

Such cases, she said, "have put into question the idea that these already were dead bodies, cadavers from which organs could be transplanted". Moreover, the acceptance of the cessation of brain activity as death contradicted Catholic doctrine — which involved the "absolute and integral defence of human life" — by equating the human person with brain functions only.

Professor Scaraffia said that "on the fortieth anniversary of the new definition of brain death, it seems the discussion has re-opened both from a general scientific point of view as well as in the Catholic sphere". This in turn meant putting into question "one of the few points" on which Catholics and nonbelievers had agreed over the past few decades.

Father Federico Lombardi, the Vatican spokesman, said that Professor Scaraffia's article was "interesting and authoritative", but did not reflect the position of the Holy See or signal any change in the Magisterium, or official teaching of the Church. However Cardinal Javier Lozano Barragan of Mexico, the Vatican "health minister" as head of the Pontifical Council for the Pastoral Care of Health Care Workers, said it was a valuable contribution to a debate "in which we have to take account of international scientific research".

Francesco D'Agostino, honorary president of the National Committee on Bio-Ethics and a leading Catholic, said that the "vast majority" of scientists recognised brain death as the end of life. He was backed by Alessandro Nanni Costa, head of the National Transplant Centre, who said brain death as defined by the Harvard report in 1968 had only ever been questioned by a "very small minority" of doctors, Catholic or otherwise.