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Quite a few people have asked if we could use the book EMBRYO: A Defense of Human Life, by Robert P. George and Christopher Tollefsen, for our Pro-Life Academy. Beginning March 16, (NEXT TUESDAY!!) we’ll discuss a chapter per week from this extraordinary book. Written in plain language, it gives an excellent biological description of development, as well as the philosophical and ethical arguments in favor of the embryo’s personhood. Check it out at Amazon. Order today!

We’ll be cross-posting with the folks over at Secular Pro-Life, as this book does not appeal to religion to make a compelling case for the human identity and status of the embryo.

BONUS: Coauthor Dr. Christopher Tollefsen has agreed to be with us during the time that we are reading his book. I met Dr. Tollefsen a few years ago and think he’s a terrific guy. He’s very approachable and able to get some pretty complex material described in simple, understandable language. We should have a good time with this.

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By Popular Demand

Quite a few people have asked if we could use the book EMBRYO: A Defense of Human Life, by Robert P. George and Christopher Tollefsen, for our Pro-Life Academy. Beginning March 16, we’ll discuss a chapter per week from this extraordinary book. Written in plain language, it gives an excellent biological description of development, as well as the philosophical and ethical arguments in favor of the embryo’s personhood. Check it out at Amazon. Order soon!

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Building on the quotes from medical and biological texts posted below yesterday, there is a need to answer some common mischaracterizations of exactly what a human embryo and fetus is, and what it is not. Some fundamental biology will clear up the confusion.

A commenter on the post No Handicapped Allowed has this to say,

“If I were married, and my wife were pregnant, I would want to get the amnio test, but ultimately I would have to respect her choice if she declined. I would fully support her decision to abort if there were clear (not maybe 1%) evidence of Down’s syndrome, or particularly of anancephaly. I don’t think of that as killing a baby. I think of it as removing tissue that will grow into a baby with severe disabilities, or even with no brain at all. Again, if she declined, I would have to respect her decision. The body often spontaneous miscarries such tissue — I have no problem with human intervention if the body doesn’t recognize the problem in time.”

It’s an understandable position until one sees the developmental stages.

The commenter mentions amniocentesis and the baby at that stage being mere tissue that has potential to become a baby in the future.

Typically, amniocentesis is performed between 16-20 weeks of development. By then the baby has developed substantially with all of its organ systems in place. When the term ’tissue’ is tossed around, it is almost universally used incorrectly.

16 Weeks Photo: MedicineNet.com

A Primer On the Hierarchy of the Human Body’s Organizational Levels:

Cells. There are approximately 200 distinctly different types of cells that comprise the human body.

Tissues. Different types of cells aggregate to form specialized functions and are called tissues. The human body is comprised of four main tissue types: Epithelial, Connective, Muscle, Nerve.

Organs. These are composed of two or more tissue types to perform special functions. Examples: Stomach, intestines, pancreas, liver, heart, etc.

Organ Systems. These are two or more organs that act in a coordinated fashion to perform a common function. For example the digestive system is composed of several organs, including the stomach, pancreas, sall and large intestines, etc., whose coordinate function is the digestion and absorption of nutrients.

Organism. This is the whole and complete animal, made up of all the organ systems functioning as a coordinated whole.

See these video and 4-D ultrasounds of developing embryos and fetuses at The Endowment for Human Development.

20 Weeks Photo: MedicineNet.com

It must be stressed, however, that even in the single-celled stage of development, the zygotic stage, there exists a brand new human organism, whole and complete in form and function for that developmental stage.

The same holds true for every stage thereafter. That’s because even at the single-celled stage, the zygote is intrinsically ordered toward mature organismal development and is proceeding along that trajectory. At birth, the baby lacks full maturational development, and will not attain such until adulthood. This developmental reality renders all argument to the contrary an expression of whim, of personal desire, with no bearing on the biological reality of organismal development.

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Compliments of Princeton Pro-Life

“Development of the embryo begins at Stage 1 when a sperm fertilizes an oocyte and together they form a zygote.”
[England, Marjorie A. Life Before Birth. 2nd ed. England: Mosby-Wolfe, 1996, p.31]

“Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (conception).
“Fertilization is a sequence of events that begins with the contact of a sperm (spermatozoon) with a secondary oocyte (ovum) and ends with the fusion of their pronuclei (the haploid nuclei of the sperm and ovum) and the mingling of their chromosomes to form a new cell. This fertilized ovum, known as a zygote, is a large diploid cell that is the beginning, or primordium, of a human being.”
[Moore, Keith L. Essentials of Human Embryology. Toronto: B.C. Decker Inc, 1988, p.2]

“Embryo: the developing organism from the time of fertilization until significant differentiation has occurred, when the organism becomes known as a fetus.”
[Cloning Human Beings. Report and Recommendations of the National Bioethics Advisory Commission. Rockville, MD: GPO, 1997, Appendix-2.]

“Embryo: An organism in the earliest stage of development; in a man, from the time of conception to the end of the second month in the uterus.”
[Dox, Ida G. et al. The Harper Collins Illustrated Medical Dictionary. New York: Harper Perennial, 1993, p. 146

“Embryo: The early developing fertilized egg that is growing into another individual of the species. In man the term ’embryo’ is usually restricted to the period of development from fertilization until the end of the eighth week of pregnancy.”
[Walters, William and Singer, Peter (eds.). Test-Tube Babies. Melbourne: Oxford University Press, 1982, p. 160]

“The development of a human being begins with fertilization, a process by which two highly specialized cells, the spermatozoon from the male and the oocyte from the female, unite to give rise to a new organism, the zygote.”
[Langman, Jan. Medical Embryology. 3rd edition. Baltimore: Williams and Wilkins, 1975, p. 3]

“Embryo: The developing individual between the union of the germ cells and the completion of the organs which characterize its body when it becomes a separate organism…. At the moment the sperm cell of the human male meets the ovum of the female and the union results in a fertilized ovum (zygote), a new life has begun…. The term embryo covers the several stages of early development from conception to the ninth or tenth week of life.”
[Considine, Douglas (ed.). Van Nostrand’s Scientific Encyclopedia. 5th edition. New York: Van Nostrand Reinhold Company, 1976, p. 943]

“I would say that among most scientists, the word ’embryo’ includes the time from after fertilization…”
[Dr. John Eppig, Senior Staff Scientist, Jackson Laboratory (Bar Harbor, Maine) and Member of the NIH Human Embryo Research Panel — Panel Transcript, February 2, 1994, p. 31]

“The development of a human begins with fertilization, a process by which the spermatozoon from the male and the oocyte from the female unite to give rise to a new organism, the zygote.”
[Sadler, T.W. Langman’s Medical Embryology. 7th edition. Baltimore: Williams & Wilkins 1995, p. 3]

“The question came up of what is an embryo, when does an embryo exist, when does it occur. I think, as you know, that in development, life is a continuum…. But I think one of the useful definitions that has come out, especially from Germany, has been the stage at which these two nuclei [from sperm and egg] come together and the membranes between the two break down.”
[Jonathan Van Blerkom of University of Colorado, expert witness on human embryology before the NIH Human Embryo Research Panel — Panel Transcript, February 2, 1994, p. 63]

“Zygote. This cell, formed by the union of an ovum and a sperm (Gr. zyg tos, yoked together), represents the beginning of a human being. The common expression ‘fertilized ovum’ refers to the zygote.”
[Moore, Keith L. and Persaud, T.V.N. Before We Are Born: Essentials of Embryology and Birth Defects. 4th edition. Philadelphia: W.B. Saunders Company, 1993, p. 1]

“The chromosomes of the oocyte and sperm are…respectively enclosed within female and male pronuclei. These pronuclei fuse with each other to produce the single, diploid, 2N nucleus of the fertilized zygote. This moment of zygote formation may be taken as the beginning or zero time point of embryonic development.”
[Larsen, William J. Human Embryology. 2nd edition. New York: Churchill Livingstone, 1997, p. 17]

“Although life is a continuous process, fertilization is a critical landmark because, under ordinary circumstances, a new, genetically distinct human organism is thereby formed…. The combination of 23 chromosomes present in each pronucleus results in 46 chromosomes in the zygote. Thus the diploid number is restored and the embryonic genome is formed. The embryo now exists as a genetic unity.”
[O’Rahilly, Ronan and Müller, Fabiola. Human Embryology & Teratology. 2nd edition. New York: Wiley-Liss, 1996, pp. 8, 29. This textbook lists “pre-embryo” among “discarded and replaced terms” in modern embryology, describing it as “ill-defined and inaccurate” (p. 12}]

“Almost all higher animals start their lives from a single cell, the fertilized ovum (zygote)… The time of fertilization represents the starting point in the life history, or ontogeny, of the individual.”
[Carlson, Bruce M. Patten’s Foundations of Embryology. 6th edition. New York: McGraw-Hill, 1996, p. 3]

“[A]nimal biologists use the term embryo to describe the single cell stage, the two-cell stage, and all subsequent stages up until a time when recognizable humanlike limbs and facial features begin to appear between six to eight weeks after fertilization….
“[A] number of specialists working in the field of human reproduction have suggested that we stop using the word embryo to describe the developing entity that exists for the first two weeks after fertilization. In its place, they proposed the term pre-embryo….
“I’ll let you in on a secret. The term pre-embryo has been embraced wholeheartedly by IVF practitioners for reasons that are political, not scientific. The new term is used to provide the illusion that there is something profoundly different between what we nonmedical biologists still call a six-day-old embryo and what we and everyone else call a sixteen-day-old embryo.
“The term pre-embryo is useful in the political arena — where decisions are made about whether to allow early embryo (now called pre-embryo) experimentation — as well as in the confines of a doctor’s office, where it can be used to allay moral concerns that might be expressed by IVF patients. ‘Don’t worry,’ a doctor might say, ‘it’s only pre-embryos that we’re manipulating or freezing. They won’t turn into real human embryos until after we’ve put them back into your body.'”
[Silver, Lee M. Remaking Eden: Cloning and Beyond in a Brave New World. New York: Avon Books, 1997, p. 39]

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Six week old human embryo. Photo:Getty

Chris, a commenter in the embryonic stem cell post passes along these great quotes from medical texts. Many thanks Chris!

“Zygote. This cell, formed by the union of an ovum and a sperm (Gr. zyg tos, yoked together), represents the beginning of a human being. The common expression ‘fertilized ovum’ refers to the zygote.”
– Before We Are Born: Essentials of Embryology and Birth Defects. 4th ed. 1993, p. 1

“The chromosomes of the oocyte and sperm are…respectively enclosed within female and male pronuclei. These pronuclei fuse with each other to produce the single, diploid, 2N nucleus of the fertilized zygote. This moment of zygote formation may be taken as the beginning or zero time point of embryonic development.”
– Human Embryology. 2nd edition. 1997, p. 17

“Although life is a continuous process, fertilization is a critical landmark because, under ordinary circumstances, a new, genetically distinct human organism is thereby formed…. The combination of 23 chromosomes present in each pronucleus results in 46 chromosomes in the zygote. Thus the diploid number is restored and the embryonic genome is formed. The embryo now exists as a genetic unity.”
Human Embryology & Teratology. 2nd edition. 1996, pp. 8, 29.

“In this text, we begin our description of the developing human with the formation and differentiation of the male and female sex cells or gametes, which will unite at fertilization to initiate the embryonic development of a new individual. … Fertilization takes place in the oviduct … resulting in the formation of a zygote containing a single diploid nucleus. Embryonic development is considered to begin at this point… This moment of zygote formation may be taken as the beginning or zero time point of embryonic development.”
Essentials of Human Embryology 1998 1-17.

“[The Zygote] results from the union of an oocyte and a sperm. A zygote is the beginning of a new human being. Human development begins at fertilization, the process during which a male gamete or sperm … unites with a female gamete or oocyte … to form a single cell called a zygote. This highly specialized, totipotent cell marks the beginning of each of us as a unique individual.”
The Developing Human: Clinically Oriented Embryology, 6th ed. 1998, pg. 2-18.

“Fertilization is an important landmark because, under ordinary circumstances, a new, genetically distinct human organism is thereby formed… Fertilization is the procession of events that begins when a spermatozoon makes contact with a secondary oocyte or its investments… The zygote … is a unicellular embryo…”
Human Embryology & Teratology 1996 pg. 5-55.

To these I add this one:

Developmental Biology by Scott Gilbert is arguably the leading text in the field. Gilbert is on faculty at Swarthmore College.

“Traditional ways of classifying catalog animals according to their adult structure. But, as J. T. Bonner (1965) pointed out, this is a very artificial method, because what we consider an individual is usually just a brief slice of its life cycle. When we consider a dog, for instance, we usually picture an adult. But the dog is a “dog” from the moment of fertilization of a dog egg by a dog sperm. It remains a dog even as a senescent dying hound. Therefore, the dog is actually the entire life cycle of the animal, from fertilization through death.”

If that can be said with such certainty of one vertebrate, it can be said of all vertebrates.

Hope these are helpful. We’ll be building on them in the future.

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Perhaps if the Justices in Ireland had read George and Tollefsen’s monumental, yet very readable work, Embryo: A defense of Human Life, they would have avoided handing down their recent catastrophic decision.

In ruling that human embryos are not human persons, the justices have decided that personhood is not an essential, intrinsic attribute of being, but rather an accidental attribute that comes and goes based upon some arbitrary criteria. This mistake now takes Ireland one very long step down the road toward more liberalized laws on abortion, euthanasia, and physician-assisted suicide. The rest of the story here.

In the particular case before them, parental rights over frozen embryos, the true horror of in vitro fertilization manifests itself. Parents treat their offspring as mere property, to be disposed of at whim. This happens way before they get to the stage of storing the ‘leftovers’ in liquid nitrogen. The process of embryo sorting, looking for the most fit, occurs right after fertilization. In order to accomplish this, the embryo needs to defined out of the human family.

Medical textbooks used to define pregnancy as beginning with fertilization. To accommodate the abortafacient reality of the birth control pill and to accommodate IVF, the definition has been changed to pregnancy defined by implantation. Changing definitions does not change objective reality, but it does clear the way for big business.

The truth is that good parents do all within their power to facilitate each of their children’s growth and development. Liquid nitrogen cold storage is the greatest of all molestations. Winnowing the offspring for keepers is extreme narcissism, if not downright diabolical. But as human history teaches, once one is defined out of the human family, anything goes.

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