be a moratorium on the cloning of a person? What are the implications of doing so? Of not doing so? If a moratorium is enacted, when should the issue be re-evaluated?

The panel’s findings with respect to these questions are presented here and are followed by our recommendations based on them.


It is a serious event when any group that has potential authority over research intercedes to ban it, and the reasons must therefore be compelling. We are convinced that the scientific and medical data concerning the likely danger to the implanted fetus or the eventual newborn if reproductive cloning of humans is attempted in the near future are very compelling.

The panel has based its support for the proposed ban on human reproductive cloning on the following findings:

Finding 1: The scientific and medical criteria used to evaluate the safety of reproductive cloning must be the potential morbidity and death of the woman carrying the clone as a fetus and of the newborn and the risk to women donating the eggs.

Finding 2: Data on the reproductive cloning of animals through the use of nuclear transplantation technology demonstrate that only a small percentage of attempts are successful; that many of the clones die during gestation, even at late stages; that newborn clones are often abnormal or die; and that the procedures may carry serious risks for the mother. In addition, because of the large number of eggs needed for such experiments, many more women would be exposed to the risks inherent in egg donation for a single cloning attempt than for the reproduction of a child by the presently used in vitro fertilization (IVF) techniques. These medical and scientific findings lead us to conclude that the procedures are now unsafe for humans.

Finding 3: At least three criteria would have to be fulfilled before the safety of human reproductive cloning could be established:

  1. The procedures for animal reproductive cloning would have to be improved to such an extent that the levels of observed abnormalities in cloned animals, including nonhuman primates, were no more than that seen with existing human assisted reproductive technology (ART) procedures. If that could not be achieved, researchers would have to demonstrate that humans are different from other

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