Given these basic facts of human embryology, it is easier to recognize the many scientifically inaccurate claims that have been advanced in the discussions about abortion, human embryo research, cloning, stem cell research, the formation of chimeras, and the use of abortifacients--and why these discussions obfuscate the objective scientific facts. The following is just a sampling of these current "scientific" myths.
Myth 1: "Prolifers claim that the abortion of a human embryo or a human fetus is wrong because it destroys human life. But human sperms and human ova are human life, too. So prolifers would also have to agree that the destruction of human sperms and human ova are no different from abortions--and that is ridiculous!"
Fact 1: As pointed out above in the background section, there is a radical difference, scientifically, between parts of a human being that only possess "human life" and a human embryo or human fetus that is an actual "human being." Abortion is the destruction of a human being. Destroying a human sperm or a human oocyte would not constitute abortion, since neither are human beings. The issue is not when does human life begin, but rather when does the life of every human being begin. A human kidney or liver, a human skin cell, a sperm or an oocyte all possess human life, but they are not human beings--they are only parts of a human being. If a single sperm or a single oocyte were implanted into a woman's uterus, they would not grow; they would simply disintegrate.
Myth 2: "The product of fertilization is simply a "blob," a "bunch of cells", a "piece of the mother's tissues"."
Fact 2: As demonstrated above, the human embryonic organism formed at fertilization is a whole human being, and therefore it is not just a "blob" or a "bunch of cells." This new human individual also has a mixture of both the mother's and the father's chromosomes, and therefore it is not just a "piece of the mother's tissues". Quoting Carlson:
"… [T]hrough the mingling of maternal and paternal chromosomes, the zygote is a genetically unique product of chromosomal reassortment, which is important for the viability of any species."15 (Emphasis added.)
Myth 3: "The immediate product of fertilization is just a "potential" or a "possible" human being--not a real existing human being."
Fact 3: As demonstrated above, scientifically there is absolutely no question whatsoever that the immediate product of fertilization is a newly existing human being. A human zygote is a human being. It is not a "potential" or a "possible" human being. It's an actual human being--with the potential to grow bigger and develop its capacities.
Myth 4: "A single-cell human zygote, or embryo, or fetus are not human beings, because they do not look like human beings."
Fact 4: As all human embryologists know, a single-cell human zygote, or a more developed human embryo, or human fetus is a human being--and that that's the way they are supposed to look at those particular periods of development.
Myth 5: "The immediate product of fertilization is just an "it"--it is neither a girl nor a boy."
Fact 5: The immediate product of fertilization is genetically already a girl or a boy--determined by the kind of sperm that fertilizes the oocyte. Quoting Carlson again: "…[T]he sex of the future embryo is determined by the chromosomal complement of the spermatozoon. (If the sperm contains 22 autosomes and 2 X chromosomes, the embryo will be a genetic female, and if it contains 22 autosomes and an X and a Y chromosome, the embryo will be a genetic male.)"16
Myth 6: "The embryo and the embryonic period begin at implantation." (Alternative myths claim 14 days, or 3 weeks.)
Fact 6: These are a few of the most common myths perpetuated sometimes even within quasi-scientific articles--especially within the bioethics literature. As demonstrated above, the human embryo, who is a human being, begins at fertilization--not at implantation (about 5-7 days), 14-days, or 3 weeks. Thus the embryonic period also begins at fertilization, and ends by the end of the eighth week, when the fetal period begins. Quoting O'Rahilly:
"Prenatal life is conveniently divided into two phases: the embryonic and the fetal. The embryonic period proper during which the vast majority of the named structures of the body appear, occupies the first 8 postovulatory weeks. … [T]he fetal period extends from 8 weeks to birth …"17 (Emphasis added.)
Myth 7: "The product of fertilization, up to 14-days, is not an embryo; it is just a "pre-embryo"--and therefore it can be used in experimental research, aborted, or donated."
Fact 7: This "scientific" myth is perhaps the most common error, which pervades the current literature. The term "pre-embryo" has quite a long and interesting history. (See Kischer and Irving, The Human Development Hoax: Time To Tell The Truth!, for extensive details and references.) But it roughly goes back to at least 1979 in the bioethics writings of Jesuit theologian Richard McCormick in his work with the Ethics Advisory Board to the United States Department of Health, Education and Welfare,18 and those of frog developmental biologist Dr. Clifford Grobstein in a 1979 article in Scientific American,19 and most notably in his classic book, Science and the Unborn: Choosing Human Futures (1988).20 Both McCormick and Grobstein subsequently continued propagating this scientific myth as members of the Ethics Committee of the American Fertility Society, and in numerous influential bioethics articles, leading to its common use in bioethics, theological, and public policy literature to this day. The term "pre-embryo" was also used as the rationale for permitting human embryo research in the British Warnock Committee Report (1984),21 and then picked up by literally hundreds of writers internationally, including, e.g., Australian writers Michael Lockwood, Michael Tooley, Alan Trounson--and especially by Peter Singer (a philosopher), Pascal Kasimba (a lawyer), Helga Kuhse (an ethicist), Stephen Buckle (a philosopher) and Karen Dawson (a geneticist, not a human embryologist). Note that none of these is even a scientist, with the exception of Karen Dawson, who is just a geneticist.
Oddly, the influential book by Singer, Kuhse, Buckle, and Dawson, Embryo Experimentation,22 (which uses the term "pre-embryo," and which contains no scientific references for its "human embryology" chart or its list of "scientific" terms), along with the work of theologian McCormick and frog developmental biologist Grobstein, was used in the United States as the scientific basis for the 1994 National Institutes of Heath (NIH) Human Embryo Research Report.23 That Report concluded that the "preimplantation embryo" (they, too, originally used the term "pre-embryo") had only a "reduced moral status." (Both the Warnock Report and the NIH Report admitted that the 14-day limit for human embryo research was arbitrary, and could and must be changed if necessary.) It is particularly in the writings of these and other bioethicists that so much incorrect science is claimed in order to "scientifically" ground the "pre-embryo" myth and therefore "scientifically" justify many of the issues noted at the beginning of this article. This would include abortion, as well as the use of donated or "made-for-research" early human embryos in destructive experimental human embryo research (such as infertility research, cloning, stem cell research, the formation of chimeras, etc.).
To begin with, it has been demonstrated above that the immediate product of fertilization is a human being with "46" chromosomes, a human embryo, an individual member of the human species, and that this is the beginning of the embryonic period. However, McCormick and Grobstein24claim that even though the product of fertilization is genetically human, it is not a "developmental individual" yet--and in turn, this "scientific fact" grounds their moral claim about this "pre-embryo." Quoting McCormick:
"I contend in this paper that the moral status--and specifically the controversial issue of personhood--is related to the attainment of developmental individuality (being the source of one individual) … It should be noted that at the zygote stage the genetic individual is not yet developmentally single--a source of only one individual. As we will see, that does not occur until a single body axis has begun to form near the end of the second week post fertilization when implantation is underway."25 (Emphasis added.)
Sounds very scientific. However, McCormick's embryology is already self-contradictory. Implantation takes place at 5-7 days. The "single body axis" to which he refers is the formation of the primitive streak, which begins to take place at 14 days. McCormick often confuses these different periods in his writings. But McCormick continues:
"This multicellular entity, called a blastocyst, has an outer cellular wall, a central fluid-filled cavity and a small gathering of cells at one end known as the inner cell mass. Developmental studies show that the cells of the outer wall become the trophoblast (feeding layer) and are precursors to the later placenta. Ultimately, all these cells are discarded at birth."26 (Emphasis added.)
The clear implication is that there is absolutely no relationship or interaction between these two cell layers, and so the "entity" is not a "developmental individual" yet. However, quoting Larsen:
"These centrally placed blastomeres are now called the inner cell mass, while the blastomeres at the periphery constitute the outer cell mass. Some exchange occurs between these groups. … The cells of this germ disc (the inner cell layer) develop into the embryo proper and also contribute to some of the extraembryonic membranes."27 (Emphasis added.)
Similarly, it is not factually correct to state that all of the cells from the outer trophoblast layer are discarded after birth. Quoting Moore:
"The chorion, the amnion, the yolk sac, and the allantois constitute the fetal membranes. They develop from the zygote but do not participate in the formation of the embryo or fetus--except for parts of the yolk sac and allantois. Part of the yolk sac is incorporated into the embryo as the primordium of the gut. The allantois forms a fibrous cord that is known as the urachus in the fetus and the median umbilical ligament in the adult. It extends from the apex of the urinary bladder to the umbilicus."28 (Emphasis added.)
Since scientists, in trying to "reach" young students in a more familiar language, sometimes use popularized (but scientifically inaccurate and misleading) terms themselves, the ever-vigilant O'Rahilly expresses concern in his classic text about the use of the term "fetal membranes":
"The developmental adnexa, commonly but inaccurately referred to as the "fetal membranes," include the trophoblast, amnion, chorion, umbilical vesicle (yolk sac), allantoic diverticulum, placenta and umbilical cord. They are genetically a part of the individual and are composed of the same germ layers."29 (Emphasis added.)
Consequently, it is also scientifically incorrect to claim that only the inner cell layer constitutes the "embryo proper." The entire blastocyst--including both the inner and the outer cell layers--is the human embryo, the human being, the human individual.
Finally, McCormick claims that this "pre-embryo" has not yet decided how many individuals it will become, since the cells are totipotent and twinning can still take place. Therefore, they argue, there is no "individual" present until 14-days and the formation of the primitive streak, after which twinning cannot take place.30
However, twinning is possible after 14 days, e.g., with fetus-in-fetu and Siamese twins. Quoting from O'Rahilly again:
"Partial duplication at an early stage and attempted duplication from 2 weeks onward (when bilateral symmetry has become manifest) would result in conjoined twins (e.g., "Siamese twins")."31 (Emphasis added.)
And even Karen Dawson acknowledges this as scientific fact in her article in Embryo Experimentation:
"After the time of primitive streak formation, other events are possible which indicate that the notion of "irreversible individuality" may need some review if it is to be considered as an important criterion in human life coming to be the individual human being it is ever thereafter to be. There are two conditions which raise questions about the adequacy of this notion: conjoined twins, sometimes known as Siamese twins, and fetus-in-fetu. … Conjoined twins arise from the twinning process occurring after the primitive streak has begun to form, that is, beyond 14 days after fertilization, or, in terms of the argument from segmentation, beyond the time at which irreversible individuality is said to exist. … This situation weakens the possibility of seeing individuality as something irreversibly resolved by about 14 days after fertilization. This in turn raises questions about the adequacy of using the landmark of segmentation in development as the determinant of moral status."32 (Emphasis added.)
It is unfortunate that the NIH Human Embryo Research Panel33 did not read this particular portion of the Singer et al book before making their recommendations about the moral status of the early human embryo.
The scientific fact is that there is no such thing as a "pre-embryo" in the real world. The term is a complete myth. It was fabricated out of thin air in order to justify a number of things that ordinarily would not be justifiable. Quoting O'Rahilly, who sits on the international board of Nomina Embryologica, again:
"The ill-defined and inaccurate term "pre-embryo," which includes the embryonic disk, is said either to end with the appearance of the primitive streak or to include neurulation. The term is not used in this book.34 (Emphasis added.)
Unfortunately, the convenient but mythological term "pre-embryo" will be used to "scientifically" justify several of the other "scientific" myths to follow, which in turn will be used to justify public policy on abortion and human embryo research world-wide.
Myth 8: "Pregnancy begins with the implantation of the blastocyst (i.e., about 5-7 days)."
Fact 8: This definition of "pregnancy" was initiated to accommodate the introduction of the process of in vitro fertilization, where fertilization takes place artificially outside the mother in a petri dish, and then the embryo is artificially introduced into the woman's uterus so that implantation of the embryo can take place. Obviously, if the embryo is not within the woman's body, she is not "pregnant" in the literal, traditional sense of the term. However, this artificial situation cannot validly be substituted back to redefine "normal pregnancy," in which fertilization does take place within the woman's body in her fallopian tube, and subsequently the embryo itself moves along the tube to implant itself into her uterus. In normal situations, pregnancy begins at fertilization, not at implantation. Quoting Carlson:
"Human pregnancy begins with the fusion of an egg and a sperm, but a great deal of preparation precedes this event. First both male and female sex cells must pass through a long series of changes (gametogenesis) that converts them genetically and phenotypically into mature gametes, which are capable of participating in the process of fertilization. Next, the gametes must be released from the gonads and make their way to the upper part of the uterine tube, where fertilization normally takes place. Finally, the fertilized egg, now properly called an embryo, must make its way into the uterus, where it sinks into the uterine lining (implantation) to be nourished by the mother."35 (Emphasis added.)
Myth 9: "The "morning-after pill," RU486, and the IUD are not abortifacient; they are only methods of contraception."
Fact 9: The "morning-after pill," RU486, and the IUD can be abortifacient, if fertilization has taken place. Then they would act to prevent the implantation of an already existing human embryo--the blastocyst--which is an existing human being. If the developing human blastocyst is prevented from implanting into the uterus, then obviously the embryo dies. In effect, these chemical and mechanical methods of contraception have become methods of abortion as well. Quoting Moore:
"The administration of relatively large doses of estrogens ("morning-after pill") for several days, beginning shortly after unprotected sexual intercourse, usually does not prevent fertilization but often prevents implantation of the blastocyst. Diethylstilbestrol, given daily in high dosage for 5-6 days, may also accelerate passage of the dividing zygote along the uterine tube … Normally, the endometrium progresses to the secretory phase of the menstrual cycle as the zygote forms, undergoes cleavage, and enters the uterus. The large amount of estrogen disturbs the normal balance between estrogen and progesterone that is necessary for preparation of the endometrium for implantation of the blastocyst. Postconception administration of hormones to prevent implantation of the blastocyst is sometimes used in cases of sexual assault or leakage of a condom, but this treatment is contraindicated for routine contraceptive use. The "abortion pill" RU486 also destroys the conceptus by interrupting implantation because of interference with the hormonal environment of the implanting embryo. … An intrauterine device (IUD) inserted into the uterus through the vagina and cervix usually interferes with implantation by causing a local inflammatory reaction. Some IUDs contain progesterone that is slowly released and interferes with the development of the endometrium so that implantation does not usually occur."36(Emphasis added.)
And since the whole human blastocyst is the embryonic human being--not just the inner cell layer--the use of chemical abortifacients that act "only" on the outer trophoblast layer of the blastocyst, e.g., methotrexate,37 would be abortifacient as well.
Myth 10: "Human embryo research, human cloning, stem cell research, and the formation of chimeras are acceptable kinds of research because until implantation or 14 days there is only a "pre-embryo", a "potential" human embryo or human being present. A real human embryo and a human being (child) do not actually begin unless and until the "pre-embryo" is implanted into the mother's uterus."
Fact 10: These claims are currently being made by bioethicists, research scientists, pharmaceutical companies, and other biotech research companies--even by some members of Congress. However, they too are "scientific" myths.
Scientifically it is perfectly clear that there is no such thing as a "pre-embryo," as demonstrated in Fact 7. As demonstrated in the background material, the immediate product of fertilization is a human being, a human embryo, a human child--the zygote. This zygote is a newly existing, genetically unique, genetically male or female, individual human being--it is not a "potential" or a "possible" human being. And this developing human being is a human being, a human embryo, a human child whether or not it is implanted artificially into the womb of the mother.
Fertilization and cloning are different processes, but the immediate products of these processes are the same. The immediate product of human cloning would also be a human being--just as in human fertilization. It is not a "pre-embryo" or a "potential" human embryo or human being. Stem cell research obtains its "stem cells" by essentially exploding or otherwise destroying and killing a newly existing human blastocyst who is, scientifically, an existing human being. The formation of chimeras, i.e., the fertilization of a gamete of one species (e.g., a human oocyte) with the gamete of another species (e.g., a monkey sperm) also results in an embryo that is "half-human." All of these types of research have been banned by most countries in the world. And all of these types of research are essentially human embryo research--for which the use of federal funds has been banned.
Myth 11: "Certain early stages of the developing human embryo and fetus, e.g., during the formation of ancestral fish gills or tails, demonstrates that it is not yet a human being, but is only in the process of becoming one. It is simply "recapitulating" the historical evolution of all of the species." Fact 11: This "scientific" myth is yet another version of the "potential," "possible," "pre-embryo" myths. It is an attempt to deny the early human embryo its real identity as a human being and its real existence. But quoting once again from O'Rahilly:
"The theory that successive stages of individual development (ontogeny) correspond with ("recapitulate") successive adult ancestors in the line of evolutionary descent (phylogeny) became popular in the 19th century as the so-called biogenetic law. This theory of recapitulation, however, has had a "regrettable influence in the progress of embryology" (citing de Beer). … Furthermore, during its development an animal departs more and more from the form of other animals. Indeed, the early stages in the development of an animal are not like the adult stages of other forms, but resemble only the early stages of those animals."38 Hence, the developing human embryo or fetus is not a "fish" or a "frog," but is categorically a human being--as has been already demonstrated.