Inspired by recent ultrasounds of our tiny child resting peacefully in utero, last month I shared my response to a common abortion-rights argument: “It’s my body; it’s my choice.” In that post, I argued that, in no way could an embryo or fetus be considered the mother’s body, or even part of the mother’s body.

The question remains, then: what is it? A few possibilities come to mind: it may be a bit of foreign debris or tissue; it may be a tumor (benign or malignant); it may be nonhuman organism (like a parasite or symbiotic microorganism); or, it may be Homo sapiens – a human organism. I’ll address these possibilities one at a time:

• Foreign debris or foreign tissue. If an embryo were nothing more than a bit of foreign matter that had somehow found its within the woman, it makes sense that her body would respond accordingly, targeting the embryo in the same way it might a sliver or a piece of shrapnel, either to eliminate it from the body or encapsulate and neutralize it. Of course, an embryo consists of living cells, so the body does not react to it as thought it were a simply a foreign object. If an embryo were living, foreign tissue, it makes sense that the woman’s immune system might react negatively to it, in the same way that it might reject a donor organ. In fact, in the vast majority of cases, the woman’s body does the opposite, suppressing it’s own immune system and laboring to provide a protective, nurturing environment and nutrients to encourage growth and development of the embryo. It is true that in certain cases (e.g., an Rh-negative mother carrying an Rh-positive fetus), the woman’s immune system may react to presence of Rh-factor in the fetus’s blood, sometimes leading to death of the fetus – however, most of the population (approximately 85 percent, I believe) is Rh-positive, so such a reaction is certainly not the norm. Nor does it change the fact that the woman’s body continues to try to accomodate the fetus even as antibodies in her blood attack the fetus’s red blood cells.
• Benign or malignant tumor. I’ve heard it more than once “It’s just a ball of cells.” Actually, I did a little reading for this post to help ensure I’m using the right terminology, and learned that tumors are more commonly defined as a neoplasm that has formed a “lump” – and a neoplasm is a new and abnormal growth or proliferation of cells not coordinated with the body’s healthy tissue. Is an embryo a neoplasm? It is certainly a new proliferation of cells, but typically (left to its own devices), its growth is in clockwork coordination with the healthy tissue around it; in fact, the surrounding, healthy tissues of the woman’s body (left to their own devices) change to become more accommodating to the new growth – again, encouraging growth and development. To quote Arnold Schwarzenegger in Kindergarten Cop: “It’s not a tumah!“
• Parasite or other nonhuman organism. An embryo or fetus certainly derives nutrients and protection, and at some cost the woman in whose body it resides – but is it a parasite (like a tapeworm) or some other symbiotic nonhuman organism (like our gut flora and other bacteria that exist on or in our body and are beneficial or neutral to our health and well-being)? First, consider that non-human organisms (parasitic or otherwise) are not native to us nor do they spontaneously generate within us. Instead, they are acquired. Even our gut flora are acquired at birth and rapidly afterward, from our mothers and the environment. An embryo, on the other hand, is not something caught from another person or acquired from the environment which then colonizes the uterus. And while it takes the introduction of a male gamete to fertilize an egg and ultimately form an embryo, even sperm cells cannot be considered parasites or symbiotic organisms – they have a short-life span and cannot reproduce themselves or “colonize” the woman on their own; those that do not fertilize an egg ultimately die off and are eliminated.
• Human organism. To review, start where you like: a zygote, an embryo, or a fetus. Clearly these are not non-living things; they are living cells that use nutrients and multiply. If it were merely foreign tissue or an infection, the woman’s body would work to destroy it – no abortion necessary. If it were a parasite or symbiotic organism, it would be acquired externally, not formed internally from two cells whose sole function is reproduction. Now, consider that when a sperm and egg unite and form a zygote, the result is genetically identifiable as human – 23 pairs of chromosomes is the norm, but even some variation in this number (as in the case of Down Syndrome), when permitted to develop, can result in a viable independent organism that we would recognize as human. Some will argue that a skin cell, or an eyelash, or a cancer cell might be alive and genetically human, but we kill those all the time; certainly that isn’t murder, is it?  Of course not. But as we’ve already established, an embryo clearly is not any part of the woman’s body (it’s not even a genetic match) nor is it a tumor (it is developing in coordination with the woman’s body and the result will be a viable, independent human organism). Without a doubt, an embryo is a living, human organism.