Novel mechanisms of reproduction: preimplantational ectogenesis.

The polarization of attitudes concerning preimplantational ectogenesis, combined with the fact that the field is technically in its infancy, makes likely the passage of much time before the use of ectogenesis becomes widespread either clinically or as a research tool. It is to be hoped that during this interval a properly critical attitude will lead to slow, steady progress while society readjusts some basic philosophic concepts.