7 reasons why a foetus is not a parasite
1. Different species
Parasitism is defined by one species feeding off another. In the case of pregnancy, the unborn offspring is not a different species, but belongs to the same species as the mother. Thus, it does not fit this description. However, I understand that there are some who assert that a foetus is not a human. This will be addressed in point 4.
2. Non-mutual relationship
Parasitism, unlike symbiosis, is characterized by being non-mutual. Biological non-mutualism is a relationship that is characterized by a species feeding off another’s bodily resources, going against the natural biological adaptation of the species it lives in or on. This defines the biological relationship between the two living entities as parasite-host. In the case of a foetus, the biological relationship is not non-mutual.
Although the foetus is dependent on the mother for life, it is not biologically non-mutual, as there is an organ (the uterus) that is specifically for the purpose of feeding and catering for the foetus. If, for example, there was an organ specifically there for the purpose of supplying blood and nutrients to fleas, then technically, if fleas were to feed on this, it would not be parasitism. As it happens, there isn’t one- the body is not designed to host fleas, lice, worms, or any parasite. The female body is, however, designed with a uterus- which does feed the foetus. Thus, pregnancy is not non-mutual.
3. Transmission
Parasites are transmitted externally. They are not developed internally, within the host’s body. A parasite exists prior to existing in it’s host.
According the Encylcopaedia Britannica, there are three types of parasites (referenced from the article “parasite”
http://www.britannica.com/EBchecked/topic/443191/parasitism):
Ectoparasites, which live on the body, and there are two types of endoparasites-
intercellular endoparasites, which inhabit spaces between cells, within the host’s body and
intracellular endoparasites, which literally live inside a cell of a host’s body.
The closest a foetus comes to, would be an intercellular endoparasite, as it inhabits the uterus (it does not live on the outside of the woman’s body, nor does it live inside a cell). Although, as mentioned in point 2, the uterus’ function is to “host” a foetus, so technically, it is not unnatural for the woman’s body to have this inside of her- the whole concept of a parasite is an organism that is not meant to be there, according to the nature of the host.
However, by contrast to intercellular endoparasites, a foetus is not “transmitted” by a “carrier” or “vector”- the father does not classify as one, because the “parasite” (the foetus) does not exist, when his penis enters the woman during intercourse. What enters the woman is sperm. The foetus results from sperm and egg meeting. Thus, a foetus, which is not transmitted externally, but develops internally, fails to comply with this definition. Sexual intercourse, the act that would result in pregnancy, is not classified as medical transmission of a parasite. Thus, a foetus is not a parasite.
4. Development
A parasite, inside it’s host, develops into nothing more than it’s species. Let’s assume a foetus is not human- in which case, you might argue that it is not the same species as it’s mother. Though I am curious as to what exactly it is, if it is not a human. But, for now, assuming that a foetus is not a human- then that means it develops into a human being. But a parasite never develops into another species- it remains the same species it always is.
I’ll admit this point is not the strongest, as parasites can develop in some ways, inside their hosts. But this point is mainly in response to those who claim that a foetus is not human. Human, biologically speaking, is a species, so to deny a foetus is a human would mean that a foetus is a different species. Even if this were true, it clearly develops into a human, but no parasite has ever been observed to develop into a different species.
5. Intrinsic principle
I will have to admit, this argument is more philosophical than scientific. By intrinsic principle, a foetus should not be killed, as it defeats the principle of reproduction.
However, a parasite, in principle, is harmful. Reproduction is supposed to happen, as a biological necessity. Parasitism is not, at least, for the host, supposed to happen. A parasite is intrinsically bad. Intrinsic value is vital to consider in ethics. If something is intrinsically bad, it is absolutely and necessarily bad, and in principle, needs to be destroyed. This is the principle of a parasite. A foetus, in principle, is not intrinsically bad, and does not need to be destroyed. Thus, it fails to fulfil the same principle that defines a parasite.
6. Parasitism does not benefit the host, and is not a natural necessity.
One of the fundamental defining features of a parasite, which distinguishes it from symbiosis, is the harm, or lack of benefit that it gives to it’s host. A parasite is thus, intrinsically bad (as mentioned in the latter point), and in principle, should be got rid of. Now, a foetus does feed off a mother’s body, and this is often cited as the first, or only, reason for why a foetus is a parasite. But as mentioned in point 2, the relationship is not non-mutual. The benefits of a parasite infestation are none. The benefits of pregnancy, however, are obvious- the continuation of the species.
Pregnancy is a natural necessity- animals/humans need to reproduce, in order to continue their species. Parasitism, however, is not a natural necessity for the host- it may be for the parasite, but not for the host. Due to the mandatory and beneficial nature of pregnancy, it is not true to say that pregnancy does not benefit anyone. You may argue it does not directly benefit the mother, per se, but it certainly does benefit the species, and it is necessary. A species does not need to be infected by a parasite, however- the principle of parasitic infection is intrinsically harmful or unbeneficial and unnecessary.
7. Pregnancy is not a disease or infestation
The encyclopaedia of science defines a disease as:
“A disturbance of normal bodily function in an organism.”
Here, we see that a disease is an
abnormal biological condition.
A parasite infestation is a disease, or an unhealthy or abnormal condition of the body. A parasite infestation is a type of disease, because it is abnormal and harmful to the host.
Thus, if a foetus were truly a parasite medically, then pregnancy would technically be classified as a disease. However, the encyclopaedia of science defines pregnancy as:
In humans the nine-month period from the fertilization and implantation of an ovum (egg), the development of embryo and fetus through the birth of a child
A disease is something that, in principle, endangers the life of an animal, and should be got rid of (thus, this point relates to point 5). Again, in principle, pregnancy is not intrinsically dangerous, and in fact, is necessary for the survival and continuation of a species. Thus, a pregnancy is not a disease or an infestation, as it is not an abnormal condition, neither is it intrinsically harmful. All parasites infestations, however, are diseases, because they are harmful, or else abnormal. Thus, a foetus is not a parasite.
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