Ethics and the future of preimplantation genetic diagnosis.

The future growth of preimplantation genetic diagnosis (PGD) will depend on refinements in genetic knowledge and genetic analysis of blastomeres. Equally important, however, is an acceptance of the ethical legitimacy of parents using technologies to select genetic traits of offspring. Objections based on embryo status, the giftedness of reproduction, eugenics, and protecting the child's welfare are not convincing grounds to oppose most uses of PGD. Whether PGD should be accepted for new medical or non-medical uses should depend upon a careful assessment of the proposed use's importance to the person or couple requesting it, and the harmful effects, if any, which it might cause. Such an approach leads to the conclusion that most new medical uses of PGD and some non-medical uses should be permitted.