Hydatidiform moles and teratomas confirm the human identity of the preimplantation embryo.

Results of recent research on hydatidiform moles and teratomas show that during pregnancy the embryo does not receive any message or information from the mother able to control the mechanisms of development or to produce the type of cellular differentiation necessary for building the tissues of the new human adult. Thus, the biological identity of the new human being does not depend on the sojourn in the uterus; the preimplantation embryo is the same individual of the human species as the adult, into whom the embryo can in principle develop.