This position includes a number of Catholic moral theologians; see, for example, Shannon, T.A., and Walter, A.B., "Reflections on the Moral Status of the Pre-Embryo." Theological Studies 51: 603-26 (1990); Cahill, L. S., "The Embryo and the Fetus: New Moral Contexts." Theological Studies 54: 124-42 (1993). Most mainline Protestants hold a developmental view; see, for example, Peters, T., For the Love of Children. pp.96-100. (Louisville, KY: Westminster, John Knox Press, 1996). In Jewish tradition, while not "mere tissue," the fetus prior to forty days development is categorized differently than it would be later. Siegel, S., "Fetal Experimentation" in Contemporary Jewish Ethics (Kellner, M., ed.) 289 (1978).