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Scientific and medical research—including stem cell research—is important and valuable work, but this research must be conducted within ethical boundaries that respect the equal dignity of all human beings. Here's why research that requires the destruction of human embryos should be rejected.

Baby boy adopted as an embryo

This baby was adopted as an embryo

Why embryos should not be destroyed


The destruction of human embryos for embryonic stem cell (ESC) research should be opposed for two reasons.


First, it is unnecessary. Research with adult stem cells, which is ethically unproblematic because it does not involve the destruction of human life, has already led to successful treatments for patients with dozens of different conditions. By contrast, ESC research has yet to produce any successful human treatments. Moreover, induced pluripotent stem cells (iPSCs) seem to offer the same theoretical benefits as ESCs—they are pluripotent and can be genetically matched to a potential patient (like ESCs from cloned embryos)—but without any ethical controversy.


Second, ESC research is unethical because it requires the killing of human embryos. As a matter of biological fact, a human embryo—whether a result of natural fertilization, in vitro fertilization, or somatic cell nuclear transfer (cloning)—is a distinct, living, and whole (though immature) human organism. The embryo is an individual member of the species Homo sapiens at the embryonic stage of his or her development. Each of us was once an embryo.


"An important fact of embryology that is crucial for you to know," explains Dr. Micheline Mathews-Roth of Harvard Medical School, "is that each member of the human species indeed starts his or her existence as one cell, the zygote; and that this fact applies whether the zygote was formed by the union of egg and sperm in the mother's body, or in a petri dish in the process of [in vitro fertilization], or by the processes of reproductive or therapeutic cloning."


Moreover, all human beings—regardless of age, size, appearance, location (e.g., a petri dish), and method of creation—have intrinsic value and deserve respect. They are not raw material to treat as a mere means to an end. They should not be killed so that their parts can be used for the theoretical benefit of others.


So-called "therapeutic cloning"—creating cloned human embryos to destroy for their stem cells—is even worse than ordinary embryo-destructive research (which utilizes leftover embryos from fertility clinics). Cloning is the deliberate manufacturing of human beings solely in order to exploit and destroy them. It is a total commodification of human life.


Cloning also requires harvesting large numbers of eggs from women. This process poses risks to women's health and can threaten their future fertility. And the offer of payment for eggs can lead to the exploitation of low-income women.


Answering the arguments for embryo destruction


Proponents of embryo-destructive research tout the potential medical benefits of such research. But these benefits are largely speculative and overstated—no successful treatments have yet been developed using embryonic stem cells—while alternative research with adult stem cells has already proven highly successful. Regardless, even the best goal cannot justify any means. No one would consider killing and harvesting useful parts from mentally disabled adults, even if it would save the lives of many other people. If embryos are valuable human beings, like disabled adults, then killing them for research, even to achieve an admirable goal, is unjust.


Another popular justification for embryonic stem cell research is that there are many "spare" or "excess" embryos—left over from in vitro fertilization—that will likely be frozen indefinitely or thrown away. Rather than discarding them, advocates argue, we ought to use them for research that could benefit others. But this argument fails for multiple reasons.


First, leftover embryos need not be discarded or killed for research—they can be adopted by loving parents. In an embryo adoption, an embryo is transferred into the uterus of an adoptive mother and given the opportunity to grow up. This is a life-giving option for infertile couples and couples wishing to adopt, and it offers embryos a chance at life. The Snowflakes Embryo Adoption Program and others like it have facilitated the adoption of thousands of frozen human embryos.


Second, even assuming that embryos will die anyway, we are not justified in slicing them up for experimentation. No one suggests that we kill and extract organs from terminally ill patients, death row inmates, or dying soldiers on the battlefield, even though they are "going to die anyway." Human beings ought to be treated with dignity and respect, not farmed for their useful parts.


Related articles:

Stem cell research and human cloning

The embryo rescue argument fails to show that some humans are expendable

The case against abortion

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