A post in today’s Secondhand Smoke reminded me of the importance of using the word “embryo” to refer to human life from conception through the eighth week of development, when it is called a fetus. In the post blog author, attorney, and bioethicist Wesley J. Smith provides an interesting quote from “The Triumph of the Pre-Embryo: Interpretations of the Human Embryo in Parliamentary Debate Over Embryo Research,” published in Social Studies of Science, Vol. 24, No. 4 (Nov., 1994, 611-639):
The spread of the term “pre-embryo” helped to resolve the moral problem of embryo research by convincing people and/or by enabling them to express their conviction that this was not, after all, research on human beings, but experimental use of an unformed, albeit human, bio mass.
This quote made me recall something I had seen earlier in Christian Faith and Human Beginnings: Christian Care and Pre-Implantation Human Life, produced by my denomination’s Commission on Theology and Church Relations (2005). In Part One, Human Beginnings, in a section called “Stages of Development,” we have the following definitions (pp. 17-18):
Embryo: A stage of pre-natal mammalian development that (in humans) extends from 2 to 8 weeks after fertilization. It is termed a ‘bilaminar’ or two-layer embryo during its second week and becomes a trilaminar (three-layer) embryo during its third week. At 9 weeks it is called a fetus. The word ‘embryo’ is also used generally to speak of all the early stages of development.
Pre-embryo: A term popularized by many writers, almost all of whom are not scientists. It refers to a zygote, morula (8 cells), blastocyst, or embryo before it develops a ‘primitive streak.’
True, in the glossary (p. 49), we find this definition of an embryo, which according to a footnote (p. 48) was derived from the National Institutes of Health:
Embryo—In humans, the developing organism from the time of fertilization until the end of the eighth week of gestation, when it becomes known as a fetus.
A list of noted embryologists, physicians, scientists, clinicians, etc. affirming the use of the word embryo beginning at fertilization can be found at “Life Begins at Fertilization with the Embryo’s Conception” at Princeton University’s Web site.
Further, the National Institutes of Health’s Stem Cell Web site provides this definition of embryo:
Embryo—In humans, the developing organism from the time of fertilization until the end of the eighth week of gestation, when it is called a fetus.
It’s possible that “The Stages of Development” section was not cross-checked with the glossary during the editing process, or that since the document was written the word pre-embryo has fallen out of use.
Nevertheless, I appreciate the Commission’s intent to speak to the public square in this document, and will send a copy of my findings to them.
