"New Age" Human Embryology Text Book:
"Pre-embryo", "Pregnancy" and Abortion Counseling; Implications for Human Embryo and Fetal Research

B. Shifting definitions of related scientific terms

A comparison of several of the basic definitions related to the terms "pre-embryo" and "abortion" that Moore uses in the third and fifth editions will demonstrate considerable contradiction and confusion. These shifting definitions would subtly support his inclusion of the erroneous term "pre-embryo" in that later edition. Once the early human embryo is relegated to a non-person, i.e., a "pre-embryo", then it is logical to give the sort of abortion counseling which is also found in the text.

In comparing the two editions, an attempt will be made to determine during which time period this supposed "pre-embryo" might exist, as well as when the "embryo" begins to exist. In analyzing these texts, there seems to be an effort to dissociate and eliminate from the fifth edition any terminology which would indicate an integral relationship between the developing human before the embryonic period as well as after the embryonic period. Additionally, it is practically impossible to determine from these texts exactly when the embryo itself actually begins. Even a comparison of the differences in the titles of the various chapters in the Table of Contents is instructive:


Third Edition

Table of Contents (pp. ix-x)

Fifth Edition

Table of Contents (pp. vii-viii)

Note that in the third edition, the clear unambiguous term "embryo" is used in both the second and third weeks. That is, in chapter three the subject is the bilaminar embryo; in chapter four the subject is the trilaminar embryo. However, in the fifth edition, the clear unambiguous term "embryo" is not used until chapter four which concerns the third week only, where the subject is the formation of the "human embryo". Note also that the "embryonic period" is from 4-8 weeks in the third edition; the fifth edition does not mention the "embryonic period" at all.

In reference to the fifth edition, does this mean that before three weeks (21 days) there is no embryo - i.e., a "pre-embryo"? And in reference to the third edition, how can the embryonic period be from 4-8 weeks, when it has already begun at 2 (or 3) weeks? Why doesn't the embryonic period start when the embryo starts - at 2 (or 3) weeks? Would the "pre-embryo" be from fertilization to 2 weeks, 3 weeks or up to the beginning of the 4th week (28 days)? So far the candidates for the "pre-embryo" period are 2 weeks (14 days), 3 weeks (21 days), or 4 weeks (28 days). If what is before the 4th week is not an embryo, but is a "pre-embryo", then would abortion and human embryo research be permissible up to the 4th week? This would also make the "pre-embryo" period much later than the implantation stage (5-6 days) or the 14-day stage which several writers claim is the biological marker event of "personhood". So when precisely is the "embryonic period"? It is certainly not clear:


Third Edition

Introduction (p.1) Prenatal Period...Note that the most striking advances in development occur during the first eight weeks, in which the embryonic period is included.

Fifth Edition

Introduction (p.1) Prenatal Period...Study of these timetables reveals that the most striking advances in development occur during the third to eighth weeks, which is known as the embryonic period.

Thus the third edition implies that the embryonic period is included in the first 8 weeks, but not necessarily from fertilization on. The fifth edition states that the embryonic period extends from the 3rd to the 8th week - which contradicts the third edition's claim of 4-8 weeks. This, again, would allow for a "pre-embryo" either from fertilization to the 3rd week (21 days) in the fifth edition - or to the 4th week (28 days) in the third edition. Which is it? And when does an embryo begin? Either sometime during the first 8 weeks; or at the third week (21 days)? And this is a scientific text book? Even the definition of the term "embryology" - the very subject matter of these human embryo text books - is confusing. In Moore's own words:


Third Edition

Scope of Embryology (p.7)

The term embryology can be misleading; literally, it means the study of an embryo (second to eighth weeks, inclusive). However, embryology refers to the study of both the embryo and the fetus, that is, the study of prenatal development.

Fifth Edition

Scope of Embryology (p.7)

Embryology literally means the study of embryos (third to eighth weeks, inclusive); however, the term generally refers to prenatal development, i.e., the study of both embryos and fetuses ...

Here we have the third edition clearly stating that an embryo exists from 2-8 weeks (14-56 days); and the fifth edition stating that an embryo exists from 3-8 weeks (21-56 days). And in both editions, "embryology" is defined as a science which only studies embryos and fetuses - which then would not include the "developing human" from fertilization to 2, 3 or 4 weeks (depending on the page or edition) - i.e., a "pre-embryo". Aside from this contradictory and confusing scientific account of "the developing human", what science, then, would have as its subject matter "the developing human" from fertilization to the formation of the "embryo"? Is there a "new science" which would have as its subject matter the study of the "pre-embryo" only? This sounds like a new classification of the sciences.

Thus there seems to be a distancing between the time of fertilization and the embryonic period (i.e., a "pre-embryonic" period) in the fifth edition. There is also the surprising claim that the embryo itself does not begin until the third, or fourth, week - i.e. 21-28 days - a period well after even the 14-day stage of "personhood" argued for by Grobstein and McCormick (Grobstein also argues contradictorily for "personhood" at several other human embryological periods as well). That is, now the "pre-embryonic" period could literally extend up to the third or fourth week, and not just up to the time of implantation (5-7 days) or the formation of the primitive streak (14-days).

There is also a gradual shift in terminology to isolate the "embryonic period" from the later "fetal period", as well as subtle changes in references to "abortion". For brevity, let me simply set out some of the different definitions which are ultimately related to the later use of the term "pre-embryo" and of the term "abortion" in this text book:


Third Edition

1. "Abortion"

This term refers to the birth of an embryo or a fetus before it is viable (mature enough to survive outside the uterus) ...

All terminations of pregnancy that occur before 20 weeks are called abortions. About 15% of all recognized pregnancies end in spontaneous abortions (ones that naturally occur), usually during the first 12 weeks. Legal induced abortions are brought on purposefully usually by suction curettage (evacuation of the embryo and its membranes from the uterus).

Fifth Edition

1. "Abortion"

This term refers to the birth of an embryo or a fetus before it is viable (capable of living outside the uterus). Threatened abortion is a common complication in about 25% of clinically apparent pregnancies. Despite every effort to prevent abortion, about _ of these pregnancies ultimately abort.

All terminations of pregnancy that occur naturally or are induced before 20 weeks are abortions. A complete abortion is one in which all the products of conception have been expelled from the uterus. About 15% of all recognized pregnancies end in spontaneous abortions (i.e., they occur naturally), usually during the first 12 weeks. Legally induced abortions, often called elective abortions, are usually produced by suction curettage (evacuation of the embryo and its membranes from the uterus). Some abortions are induced because of the mother's poor health or to prevent the birth of a severely malformed child (e.g., one without most of its brain).


If the term "abortion" applies only to the terminations of pregnancies up to 20 weeks, does that mean that the terminations of pregnancies after 20 weeks are not to be classified as "abortions"? That's odd. What are they to be classified as? And if the term "abortion" applies only to the birth of an embryo (or a fetus), does that mean that it would not be applied to the termination of a "whatever" that comes before the "embryo" stage? In the third edition, the first part of the reference applies the term "abortion" to all terminations of pregnancy that occur before 20 weeks, which would imply that the termination of a fetus would also be considered an abortion. In the latter part of the reference, the term applies only to the embryo, and not to the fetus as well. The same is true for the fifth edition. Thus the latter parts of the definitions of the term "abortion" would not refer to either the so-called "pre-embryo" or to the fetus. Also, note the fifth edition adding reasons for induced abortions, e.g., the birth of a severely malformed child [such as an anencephalic child].


Third Edition

2. "Abortus"

This term describes any product or all products of an abortion. An embryo or a non-viable fetus and its membranes weighing less than 500 grams is called an abortus.

Fifth Edition

2. "Abortus"

This term refers to the products of an abortion (i.e., the embryo/fetus and its associated membranes, such as the amnion and chorionic sac). An embryo or nonviable fetus and its membranes weighing less than 500 grams is called an abortus, but often one refers to them as aborted embryos or fetuses.


The term "abortus", like the term "abortion", does not refer to a so-called "pre-embryo" either. It does still refer to both embryos and fetuses in both editions. But when the above term "abortion" refers only to an embryo (and not also to a fetus), then the term "abortus" could not refer to the fetus as well. Thus, if one were going by the latter part of the definition of "abortion", if a fetus were to be terminated the fetus would not be referred to as an "abortus". Thus, again, the so-called "pre-embryo" is left out of the definition of the term "abortus"; and the fetus could be left out of the term "abortus" if one wanted to use the latter terminology of "abortion".

Note also that the fifth edition now includes a reference to the "associated membranes" as inclusive of the amnion and the chorionic sac. As noted earlier, Moore was contradictory between his earlier and later chapters about the intermingling of the two cell layers of the blastocyst. In his earlier chapters he stated that all of the cells of the trophoblast layer are discarded after birth as the placental membranes, etc. In his later chapters he stated that this was true with the exception of cells from the yolk sac and allantois - cells derived from the trophoblast, both of which he later traces to the developing embryo, fetus and adult human being. In this present statement here he adds a reference to "membranes" which are part of the abortus - but neglects to mention these include the two cell types of the trophoblast which are later incorporated into the embryo, fetus and adult. The attention in this fifth edition to these membranes which were of such interest and importance to Grobstein and McCormick is interesting enough. His failure to mention the eventual destination of cells from the yolk sac and the allantois in the later fetus and adult human being, along with no mentioning at all of the amnion and the chorionic sac, is disingenuous at best.


Third Edition

3. "Zygote"

This cell results from fertilization of an oocyte, or ovum, by a sperm, or spermatozoon, and is the beginning of a human being.

Fifth Edition

3. "Zygote"

This cell results from fertilization of an oocyte by a sperm. A zygote is the beginning of a new human being.


At least Moore still acknowledges here that the zygote is the beginning of a "developing human being" (although given the above references it is an odd human being, i.e., one that is not an embryo yet). But even though he admits that fertilization marks the beginning of an individual human being, the questions for some (e.g., Grobstein and McCormick) is whether or not it is also a human "person", i.e., a "developmental individual".

It could also be very confusing for Moore to use the simplistic term "oocyte". There are primary and secondary "oocytes", and ova - all very different terms depicting different stages during oogenesis and fertilization. Since a primary oocyte has not proceeded through the first meiotic division (which won't happen until after puberty) and still contains 46 chromosomes (instead of 23 chromosomes), it cannot yet be fertilized by a sperm, and so they would not be usable yet in IVF "therapy" or in human embryo research. Given the studies proposed in Scotland to use the "eggs" from aborted female fetuses in IVF "therapies" for post-menopausal women, such a distinction would be very critical. Those "aborted eggs" cannot be fertilized or used in human embryo research or implanted, because each of them still contains 46 chromosomes and thus can not be fertilized.


Third Edition

4. "Blastocyst"

After the morula enters the uterus, a cavity develops inside it and fills with fluid; This converts the morula into a blastocyst.

Fifth Edition

4. "Blastocyst"

After the morula enters the uterus from the uterine tube, a fluid-filled cavity develops inside it; this converts the morula into a blastocyst. Its centrally located cells called the embryoblast or inner cell mass, will form the embryo.


Without repeating, the fifth edition again seems to be focusing on the issue argued by Grobstein and McCormick - i.e., that only the cells from the embryoblast (inner layer) of the blastocyst - not any of the cells from the trophoblast (outer layer) - will form the later embryo, fetus and adult human being. Yet, as already indicated, Moore contradicts those claims in his later developing chapters.


Third Edition

5. "Embryo"

This term refers to the developing human during the early stages of development. The term is usually not used until the second week, after the embryonic disc forms ... The embryonic period extends until the end of the eighth week, by which time all major structures are present.

Fifth Edition

5. "Embryo"

This term refers to the developing human during its early stages of development. The term is not usually used until the middle of the second week. The embryonic period extends to the end of the eighth week, at which time the beginnings of all major structures are present.

Here we have the embryo beginning both the "second" week, and the "middle of the second" week. And recall that the third edition contradicts its own Table of Contents in which the "embryonic period" is defined as from four to eight weeks. The fifth edition contradicts its own previous claim of 3 weeks. Both editions contradict each other.


Third Edition

6. "Fetus"

[in the Table of Contents, this stage extends from the ninth week to birth]

7. "Conceptus"

This term refers to the EMBRYO (OR FETUS) and its membranes, the products of conception. It includes all structures that develop from the zygote, both embryonic and extraembryonic. Hence it includes not only the EMBRYO OR FETUS, but also the embryonic or fetal membranes.

Fifth Edition

6. "Conceptus"

This term refers to the EMBRYO and its membranes, i.e., the products of conception or fertilization. It includes all structures that develop from the zygote, both embryonic and extraembryonic. Hence it includes the EMBRYO as well as the fetal part of the placenta and its associated membranes, e.g., the amnion and chorionic sac ...

7. "Fetus"

[In the Table of Contents, this stage extends from the ninth week to birth]


Third Edition

6. "Fetus"

[in the Table of Contents, this stage extends from the ninth week to birth]

7. "Conceptus"

This term refers to the EMBRYO (OR FETUS) and its membranes, the products of conception. It includes all structures that develop from the zygote, both embryonic and extraembryonic. Hence it includes not only the EMBRYO OR FETUS, but also the embryonic or fetal membranes.

Fifth Edition

6. "Conceptus"

This term refers to the EMBRYO and its membranes, i.e., the products of conception or fertilization. It includes all structures that develop from the zygote, both embryonic and extraembryonic. Hence it includes the EMBRYO as well as the fetal part of the placenta and its associated membranes, e.g., the amnion and chorionic sac ...

7. "Fetus"

[In the Table of Contents, this stage extends from the ninth week to birth]

Note now that while in the third edition the term "conceptus" refers to the embryo and fetus, in the fifth edition it refers only to the embryo, and not also to the fetus. Note also in the fifth edition the same elaboration of the placenta and its associated membranes (the amnion and chorionic sac) - again with no mention of the eventual destination of the cells of the yolk sac and the allantois in the later fetus and adult human being. The shift in the ordering of the terms "fetus" and "conceptus" will be addressed momentarily.

If we are not totally confused yet as to what a "pre-embryo", an "embryo", a "conceptus" or an "abortus" is - or when each of these begins to form, or what an "abortion" is (and exactly what it is that is being aborted), consider the end of Chapter One (p. 12), where (as in every chapter) there is a set of "clinically oriented problems" or "questions" prepared for the bright inquiring medical or graduate biology students.


Third Edition

Question 3: Differentiate between the terms conceptus and abortus.

Answer (p. 446): The term "conceptus" is used when referring to an embryo or a fetus and its membranes, i.e., the products of conception. The term "abortus" refers to any product or all products of an abortion, e.g., the embryo (or part of it) and/or its fetal membranes and placenta (or parts of them).

Fifth Edition

Question 3: How does a conceptus differ from an "abortus"?

Answer (p. 458): The term "conceptus" is used when referring to an embryo and its membranes, i.e., the products of conception. The term "abortus" refers to any products or all products of an abortion, e.g., the embryo (or part of it) and/or its membranes and placenta (or parts of them). An abortion, therefore is an aborted conceptus.


Now, this is really confusing. One has to wonder how these bright inquiring medical or graduate biology students ever study for their exams. First of all, neither the third edition nor the fifth edition refer to a so-called "pre-embryo", or whatever comes before the embryo (whenever that is). Thus a "pre-embryo" is not aborted, nor is it called an abortus or a conceptus. Second, in the fifth edition, now an "abortus" is an aborted "conceptus", and an aborted "conceptus" is only an embryo. That is, since a fetus is not included in the definition of a "conceptus", the term "abortus" does not apply to an abortion of a fetus either. This is why, in the listing of these terms, the third edition lists the term "fetus" before the term "conceptus", while in the fifth edition, the term "fetus" is listed after the term "conceptus". For some reason the latter part of the definition of the term "abortion", and the definitions of the terms "conceptus" and "abortus" in the fifth edition do not refer to the fetus.

Now one cannot refer to a fetus as having been aborted, or referred to as an abortus or a conceptus. If it is aborted, then what is it to be referred to as? And how could it not be considered a conceptus (i.e., the product of conception)? If it is not the product of conception, then what is it the product of? I suppose that if IVF is ever really perfected, neither the act of intercourse nor the mother's womb would be necessary, and the fetus would truly be considered the "product of IVF". Perhaps that could be the "subject matter" of the "new science" that the present science of embryology (by definition) does not study - along with the study of the "pre-embryo". "Embryology", then would really only study "embryos" - period. Eventually I suppose we could do away with all of the above related terms, since there would technically be nothing to which the terms "abortion", "abortus" or "conceptus" could refer - since no women would have to be "pregnant". Indeed, I am sure that the work on the "artificial placenta" will ensure that. What a brave new world!

Second, in the main text of the third edition, there is no difference between a "conceptus" and an "abortus"; and both terms refer to both an embryo or a fetus. Yet in this "clinically oriented question", a "conceptus" still refers to both an embryo and a fetus; but an "abortus" now refers only to an embryo. Thus the third edition is contradicting its own definitions. In the main text of the fifth edition, the term "conceptus" refers only to the embryo, and the term "abortus" refers to both the embryo and the fetus. Yet in its "clinically oriented question", both terms refer only to the embryo and not to the fetus.

Part of our confusion may be resolved, however, when we get to the "study" questions at the end of chapter two. The following question and answer do not appear in the third edition; only in the fifth edition:

Question 5 (p.38): A young woman who feared that she might be pregnant asked about the so-called "morning-after pills" ... What would you tell her? Would termination of such an early pregnancy be considered an abortion?

Answer 5(p. 458): Postcoital birth control pills ... will usually prevent implantation of the blastocyst ... Pregnancy occurs, but the blastocyst does not implant. The term abortion would not be applied to such an early termination of pregnancy.

"The term abortion would not be applied to such an early termination of pregnancy". And so, presumably, one can terminate "it" and still not have had an abortion. How is this explainable? Is it that, unless the embryo (or "pre-embryo") has implanted, then the woman is not yet "pregnant"? It would seem not, since the answer states "such an early termination of pregnancy". Thus, presumably Moore acknowledges, at least, that the woman is pregnant.

No, it would seem that it is because the woman's stage of pregnancy is "early". But what does "early" have to do with it? I would argue that just as Grobstein and McCormick use the term "pre-embryo" in order to justify experimentation on the early human blastocyst (and actually until the 14-day stage), here Moore has set up the terms with such confusion, and incorporated in this edition the erroneous term "pre-embryo", in order to justify the termination of the "early developing human being" without calling it "abortion".

Now it is scientifically justifiable to use the "morning after pills" - which Moore admits does not prevent fertilization, but only implantation - to eliminate what is basically, after all, only a "pre-embryo" - i.e., a non-person - if one is "fearful" that one is experiencing an "early" pregnancy. The term "pre-embryo", then, would also justify the use of the French abortion pill RU486. The term would also justify the use of these early developing human beings in experimental medical research.

So, amid this confusion of contradictory and inconsistent definitions and terms, the concrete result is that what most of us refer to as "abortion" is scientifically justified. "Abortion" during "early pregnancy" simply disappears. I suppose such an "early pregnancy" might be termed a "pre-pregnancy". And with these "redefinitions" goes the guilt, regrets, and moral rebukes that women may fear from the termination of these "early" pregnancies.

Note that "abortion" of a fetus also disappears. The term "abortion" no longer can be referred to the termination of a fetus; it will be restricted to the embryo only. Perhaps the termination of a fetus will be called a "post-pregnancy". Perhaps we also need to clarify exactly what is meant by the term "pregnancy". What is a "pregnancy"? Does it only have reference to the woman, and not also to what she is pregnant with? How is the critical term "pregnancy" defined?

III. "Pregnancy": The case of the missing definition

It would seem at this point that a relevant "clinically orientated question" to be addressed to those bright inquiring medical and graduate biology students is: "How would you define 'pregnancy'"? If before implantation (5-6 days) - (or 2, 3 or 4 weeks) - there is only a "pre-embryo", and therefore a "pre-pregnancy", how then does one define a "pregnancy"? After all, abortion is commonly understood as the termination of a pregnancy - right? Well, then, scientifically speaking, just when does a woman become "pregnant"?

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