As the zygote develops, nothing new is learned genetically but, progressively, many things are forgotten. These findings prove differentiation and that from the very beginning there exists a human embryo. This correct scientific understanding of human embryology and the beginning of human life recognizes that the fertilized egg is a living entity, a human being, a human individual and a person, all one and inseparable. After the initial contact of sperm and egg, there is no subsequent moment or stage which is held in arbitration or abeyance by the mother, or the embryo or fetus. Nor is a second contribution, or signal or trigger, needed from the male in order to continue and complete full development to birth.
Human development is a continuum in which so-called stages overlap and blend into one another.
Thus, the beginning of a new life is exacted by the beginning of fertilization, the reproductive event which is the essence of life. At this time, there are three proposed methods for obtaining human embryonic stem cells which warrant careful ethical analysis. It is critical to recognize that although IVF is a violation of the Laws of Nature and, hence, is unethical, what results in a glass dish from IVF are human embryos who are human beings whose dignity and right to life must be respected from the first moment of their existence. The Inner Cell Mass is removed from these human embryos at the blastocyst stage of development resulting in the death of that human life each and every time. The destruction of one human life in order to attempt to save another human life is always gravely unethical.