Preimplantation diagnosis.

Preimplantation genetic diagnosis is a valuable addition to the repertoire of reproductive medicine because it gives individuals with a documented history of a genetic disorder the opportunity to begin a wanted pregnancy with little or no fear that they are transmitting this disorder to their offspring. An outstanding example of this is the recent report of PGD being successfully used to avoid the conception of a child that could have inherited a predisposition to early-onset Alzheimer disease. However, if this service becomes embroiled in the detection of conditions having little or nothing to do with health and disease in order to satisfy patient demand or to be a profitable business, its activities will be much more ethically suspect.