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‘Pre-Embryos’ And ‘Pre-Embryo Substitutes’: Safeguarding Human Life “From The Very Beginning”?

(Today’s guest commentary was written by Dr. Dianne Irving on June 8 and posted on www.lifeissues.net. It is reprinted here with her kind permission. Dr. Irving is a former career-appointed bench research biochemist/biologist (NIH, NCI, Bethesda, Maryland), an M.A. and Ph.D. philosopher (Georgetown University, Washington, D.C.), and professor of the History of Philosophy, and of Medical Ethics.)

1. Introduction

How difficult it has been to “safeguard human life” from “the very beginning.” Indeed, especially over the last 40 years or so, the value of human life has diminished steadily and rapidly – especially with regard to its “beginning.” Yet even aside from the important and significant “personhood” debates, the Church has consistently taught that the mere fact that there is a living innocent human being before us is sufficient to safeguard the life of that human being even at its very beginning. Pope John Paul II often addressed this tragic trajectory of the loss of respect for human life, as in his encyclical Evangelium vitae:

Even if the presence of a spiritual soul cannot be ascertained by empirical data, the results themselves of scientific research on the human embryo provide "a valuable indication for discerning by the use of reason a personal presence at the moment of the first appearance of a human life: how could a human individual not be a human person?" … Furthermore, what is at stake is so important that, from the standpoint of moral obligation, the mere probability that a human person is involved would suffice to justify an absolutely clear prohibition of any intervention aimed at killing a human embryo. Precisely for this reason, over and above all scientific debates and those philosophical affirmations to which the Magisterium has not expressly committed itself, the Church has always taught and continues to teach that the result of human procreation, from the first moment of its existence, must be guaranteed that unconditional respect which is morally due to the human being in his or her totality and unity as body and spirit … [Pope John Paul II, Evangelium vitae 60, On the Value and Inviolability of Human Life (Encyclical, March 25, 1995)] (emphases added)

But precisely when is “the first moment of its existence”?!

Without doubt, the abuse of language, especially scientific “language,” has shrouded clear facts about precisely when the “first moment of its existence is,” and has hastened this drastic decline in the respect for human life. This linguistic abuse has been both purposeful as well as naively equivocal.  That is, it is not just because of the willful and devious use of language by ardent supporters of IVF and other ARTs, abortion, the use of abortifacients, human embryo and human fetal research, human cloning, and genetic engineering, etc., but also because even many of those who are dedicated to this “safeguarding” themselves fall victim to the use of erroneous “scientific” terms. The result is an amazingly long list over the decades of what I have often referred to as “pre-embryo substitutes.”

Given that this linguistic phenomenon continues unabated as we speak, it might be of help to remind ourselves of how very subtly these linguistic twists can come about so that we can be more sensitive to identifying them. Generally speaking, there are a number of ways that the misuse of simple scientific “language” can slip into our rhetoric and our thinking processes without notice.

2. The ‘Pre-Embryo’

First, it is to be noted historically that the authors of the now officially rejected false scientific term “pre-embryo,” which term has caused almost 30 years worth of a deluge of horrific and unethical medical policies and destructive research, were a Catholic Jesuit priest and a Catholic frog biologist – Fr. Richard McCormick and Clifford Grobstein. According to them, there is an important scientific and moral distinction to be made between a “human being” and a “human person.” That is, they agreed that the immediate product of fertilization was a human being (a "genetic individual"), but before 14-days it was not yet a human person (a "developmental individual") with a rational soul, and thus with the same ethical and legal rights and protections as all other human persons. Before 14-days there was just a “pre-embryo,” a “non-person” – and although it should be “respected,” it is still ethical to kill this “pre-embryo” for proportionate reasons. Of course, this “distinction” of McCormick and Grobstein between a “human being” and a “human person” – as with so many other similar “distinctions” ripe in the bioethics literature over the years – is a false distinction, a “distinction” without a real difference.

This false pseudo-scientific term “pre-embryo,” and its accompanying false term “individuality,” was finally formally rejected by the international nomenclature committee in human embryology. That committee made it clear that at fertilization (sexual human reproduction), the “embryo” begins to exist immediately. Thus, scientifically, there is no such thing as a “pre-embryo” that exists after fertilization and before 14-days. There is, rather, an already existing embryo. As famous Swiss human embryologist, as a member of that international nomenclature committee, and as major contributor to the Carnegie Stages of Early Human Embryonic Development themselves, stated bluntly in his human embryology textbooks years ago:

The term 'pre-embryo' is not used here for the following reasons: (1) it is ill-defined because it is said to end with the appearance of the primitive streak or to include neurulation; (2) it is inaccurate because purely embryonic cells can already be distinguished after a few days, as can also the embryonic (not pre-embryonic!) disc; (3) it is unjustified because the accepted meaning of the word embryo includes all of the first 8 weeks; (4) it is equivocal because it may convey the erroneous idea that a new human organism is formed at only some considerable time after fertilization; and (5) it was introduced in 1986 'largely for public policy reasons' (Biggers). … Just as postnatal age begins at birth, prenatal age begins at fertilization." [Ronan O'Rahilly and Fabiola Muller, Human Embryology & Teratology (New York: Wiley-Liss, 2001), (p. 88)] (emphases added)

Of import too is that the Carnegie Stages are professionally required to be used by all authors in their human embryology textbooks. (You will also notice the full chart of the Carnegie Stages included in these same professional scientific textbooks, as well as the Carnegie Stage numerical superscripts above the less technical renditions of them used by these authors in textbooks meant for unsophisticated students to indicate for the reader where to go to find out more detailed and refined scientific descriptions of these stages).

However, the “pre-embryo” had already been institutionalized by then (even around the world), and many on both sides of the aisle were not happy with this formal scientific refutation of their supra-useful linguistic invention. For those who wanted to pursue IVF, abortion, research, etc., they would have to come up with some other false scientific terms to scientifically “justify” what they wanted to do. And for many on the other side of the aisle the “pre-embryo” had allowed them to be perceived as more “pastoral,” more “empathetic,” more “scientifically current,” more “modern” and more popular, enabling them to “have a seat at the table.” They too would turn a blind eye at the easily accessible accurate empirical facts of human embryology known and continuously internationally documented and updated for over a hundred years – and found in libraries all over the world, even now on the internet. The temptations were overwhelming.

3. ‘Pre-embryo Substitutes’

And thus began “stage two” of this sort of verbal deception required to “scientifically” justify all manner of projects with the early human embryo. This “stage” I have often referred to as consisting of “pre-embryo substitutes.” That is, the term “pre-embryo” must now necessarily be dropped, but the same agenda could be accomplished by substituting other false “science” in its place, or simply leaving out legitimate early phases of human embryonic development as if they didn’t exist. One example of this is to claim that the “zygote” is the beginning of when a human being begins to exist. But this would render the human being already existing before the formation of the “zygote” non-existent – neither a human being nor a human person – and thus it could be used simply as “biological material,” especially in human genetic engineering research, etc. This “biological entity” is often referred to in the literature as a “pre-zygote” – that is, what is there from the beginning of fertilization up to the formation of the zygote is not a human embryo or a human being. It is just a human “cell.”

However, the Carnegie Stages of Early Human Embryonic Development make it clear that the “zygote” formed at the end of the process of fertilization is not when a new human being begins to exist. Before that, the developing embryo in Stage 1 of the Carnegie Stages begins with “first contact” of the sperm with the oocyte, followed by, respectively, the phases of development referred to as “the penetrated oocyte” and the “ootid.” In other words, the new human embryo begins to exist at first contact, at the beginning of the process of fertilization:

Fertilization, which takes place normally in the ampulla of the uterine tube [[fallopian tube]], includes (a) contact of spermatozoa with the zona pellucida of an oocyte,
penetration of one or more spermatozoa through the zona pellucida and the ooplasm, swelling of the spermatozoal head and extrusion of the second polar body, (b) the formation of the male and female pronuclei, and (c) the beginning of the first mitotic division, or cleavage, of the zygote. … The three phases (a, b, and c) referred to above will be included here under stage 1, the characteristic feature of which is unicellularity. (Carnegie Stages of Early Human Embryonic Development, p. 9) ) (emphases added)

Note especially that “first contact” is included in, but precedes, the “penetrated oocyte” of phase (a). Given the spectacular biochemical events that are tripped at the moment of first contact of the sperm with the oocyte – events that could definitely not and do not take place in either a sperm or an oocyte alone – it is clear that a new substantial change has taken place. (It is interesting that in both biology and in classic realist philosophies, the identification of a new substance is marked in the relevant texts as “function follows form,” or “action follows being! That is, radically new functions or actions follow the formation of a radically new form – which radically new form causes those new functions and actions).

Another example of leaving out specific stages of early human embryonic development can be found in several definitions in laws and regulations. A classic example is the formal definitions of “fetus” and “pregnancy” in the federal OPRR/OHRP guidelines for the use of human subjects in research as both “beginning at implantation.” (In fact, the “fetal” period does not begin until the beginning of the 9th week of development). In this example, then, there is no embryo at all – through 8 weeks, in vivo or in vitro, sexually or asexually reproduced – gone! And all women (rather than just those undergoing IVF or ART) become pregnant only at implantation; before that they are not “pregnant” (and therefore, the use of abortifacients, embryo flushing, prenatal genetic diagnosis, as well as all manner of human embryo research, are “ethical”).

Or, one can add to specific stages of early human embryonic development. In a more recent example, the order of scientific terms that should inclusively mean the embryo at all of its various early stages is shifted. Listing the term “embryo” after them, as if what came before was not an embryo, makes the embryo during those earliest of phases of development essentially disappear. Thus we have this following subtle but spurious “pre-embryo substitute” which for all the world sounds very pro-life:

Embryos are no different in their essential humanity from a fetus in the womb, a 10-year old boy, or a 100-year old woman. At every stage of development, human beings (whether  zygote, blastocyst, embryo, fetus, infant, adolescent or adult) retain their identity as an enduring being that grows toward its subsequent stage(s); embryos are integral beings structured for maturation along their proper time line.

So, to the casual observer, by adding the term “embryo” after the terms “zygote” and “blastocyst” – followed by “fetus,” “infant,” etc. – it would appear that the “zygote” and the “blastocyst” are something other than an “embryo” – i.e., not yet an embryo, not yet a human being (much less a human person). (Not to mention that the embryo formed at first contact, the “penetrated oocyte” and the “ootid” are not even listed). And importantly also, it would seem then that only embryos (which apparently doesn’t include the embryo at its earliest phases of development) “are integral beings structured for maturation along their proper time line,” etc. – and not also “zygotes” and “blastocysts.”

Again, one can make a “pre-embryo substitute” by articulating only one kind of human reproduction. For example, one can claim that all human beings begin to exist at “fertilization” or at “conception.” But by definition, that makes all human beings reproduced asexually disappear (which would include one of every set of naturally occurring human monozygotic twins in vivo, and all human embryo reproduced asexually using the various cloning techniques, genetic engineering, etc.).

Perhaps the most daring, and most successful, “pre-embryo substitute” was concocted by human cloning and human embryonic stem cell researchers Irving Weissman, Michael West, et al. While the McCormick/Grobstein “pre-embryo” at least acknowledged that the immediate product of fertilization is a human being (it is just not a human person), for these researchers the immediate product of both sexual and asexual human reproduction is “just a cell” – not a human being, not a human organism, not a human embryo. And the “blastocyst” from which “stem cells” are derived is simply “a ball of cells.” These researchers also concocted another way to get rid of the human embryo – in fact, they got rid of the human embryo and the human fetus – by making a false distinction between “therapeutic” and “reproductive” cloning. They claimed that the product of “therapeutic cloning” was just a bunch of cells; the product of “reproductive cloning” was a human being – but not until it was born! They also enjoyed defining “cloning” only in terms of somatic cell nuclear transfer (SCNT) – thus making all of the other dozens of kinds of human cloning techniques disappear.

Or, one can make other kinds of cloning techniques “disappear” linguistically by including in one definition what is really part of another cloning technique that they want to divert attention from. For example, it has been claimed that the product of SCNT is an “identical twin” of the donor (which is erroneous because of the “foreign” mitochondrial DNA left over in the enucleated oocyte used). But the real product of SCNT or GLNT (germ line nuclear transfer) is thus genetically unique (which has serious implications for patients when injecting them with “stem cells” from such cloned embryos – even if the donor cell is from the same patient). But by using the term “identical twin,” the writers
thus conflate the SCNT cloning technique with the “twinning” technique (i.e., blastomere separation, blastocyst splitting, embryo multiplication, etc.) – used now for many years in IVF/ART as “infertility treatments.” Thus to the “average” reader, SCNT and “twinning” are the same.

Indeed, such “pre-embryos” and “pre-embryo substitutes” as noted above are particularly useful in laws and regulations involving the early human embryo, because often such innovative and imaginative but false scientific terms used in legal definitions are legally “exclusionary” – and thus create useful legal loopholes. It’s enough to make our collective heads spin!

Yet very few on either side of the aisles have been paying attention – for several decades now.

4. Correct Formation of Conscience

As noted, this linguistic abuse of language concerning the early human embryo is an on-going concern, and ever new, inventive and imaginative “pre-embryo substitutes” appear almost on a daily basis. This is why it is important to be aware of and acknowledge the long-established and documented empirical facts of human embryology, for before long we will not even be able to define scientifically that point in time when we should start “safeguarding life from its very beginning.” The scientific terms or concepts that we use will have lost all meaning and relationship to reality.

And as Pope John Paul II has also warned, these linguistic twists of scientific terms and concepts have already had a devastating effect on the correct formation of conscience:

The end result of this is tragic: not only is the fact of the destruction of so many human lives still to be born or in their final stage extremely grave and disturbing, but no less grave and disturbing is the fact that conscience itself, darkened as it were by such widespread conditioning, is finding it increasingly difficult to distinguish between good and evil in what concerns the basic value of human life. … [W]e need now more than ever to have the courage to look the truth in the eye and to call things by their proper name, without yielding to convenient compromises or to the temptation of self-deception. … Perhaps this linguistic phenomenon is itself a symptom of an uneasiness of conscience. But no word has the power to change the reality of things. (Pope John Paul II, Evangelium vitae 1995, pars. 4 and 58)

Hopefully the long-known, long-documented and continuously updated accurate empirical starting point for determining when a human being begins to exist – such as those found in the Carnegie Stages and incorporated in professionally responsible human embryology and related scientific textbooks – will not be abandoned by professionals in the field of human embryology. Nothing but utter chaos would ensue.

But perhaps that is the goal.

[For more detailed references, see Irving:

— “Human Embryology and Church Teachings” (September 15, 2008)

— “The Carnegie Stages of Early Human Embryonic Development: Chart of all 23 Stages, and Detailed Descriptions of Carnegie Stages 1 – 6” (April 22, 2006)

— “Framing the Debates on Human Cloning and Human Embryonic Stem Cells: Pluripotent vs. TOTIPOTENT” (July 23, 2005)

— “Definitions of a “human organism” and a “human cell” (Oct. 3, 2004)

— “What Human Embryo? Funniest Mental Gymnastics from Medicine and Research” (Oct. 14, 2004)

— “Analysis of Legislative and Regulatory Chaos in the U.S.: Asexual Human Reproduction and Genetic Engineering” (Oct. 20, 2004),

— "The Impact of 'Scientific Misinformation' on Other Fields: Philosophy, Theology,
Biomedical Ethics, Public Policy
,” Accountability in Research, April 1993, 2(4):243-272]