Conception vs Fertilization

Conception: is not the definition of conception when the fertilized egg implants to the uterus?

Since science holds that the moment the egg and the sperm unite, a human life is started, would it be more accurate to use the term fertilization?

E.g. “A human life begins at the moment of fertilization”

It just seems to me, that if I ever came across someone who supported abortion and also was scientifically knowledgeable, this point might come up in the argument.

Yes, I’ve been arguing about abortion for 8 years and I haven’t had someone notice this, but the possibility still exists, and in the name of science, accuracy seems important.

What do you guys think? Should those who are anti-abortion and pro-life begin using the term fertilization?

I think you are splitting hairs. Part of the definition of conception is fertilization when the word is used with regard to pregnancy.

Even more to the point, conception, is the very act of becoming fertilized, the inception of a pregnancy.

So, no, I would disagree with the use of fertilization and stick with conception.

It’s a worthwhile distinction as far as it goes. Ultimately, the “best” argument in defense of abortion is an appeal to agnosticism–that we don’t know when there is a new human. Their best argument fails because of the Deerhunter principle–meaning it is immoral to shoot into rustling bushes without knowing what it is you are unleashing deadly force on.

Watch out for people who try to play various popes and Church doctors against each other over “ensoulment”. The Church has addressed this explicitly. I blogged about it here:

–If one has spent much time refuting arguments in favor of abortion, then they have likely encountered a ploy whereby various popes and prominent churchmen are pitted against each other over *ensoulment *(when newly-conceived humans receive their souls.) The defenders of The Hopeless Position “reason” that this back-and-forth demonstrates confusion in the Church over the issue, and therefore the evil of abortion is not an absolute moral norm, but merely current policy.

Bull hockey.

For a while I thought somewhere in Church documents there was something that explicitly rejects the idea that the evil of abortion stands or falls on ensoulment, but I could not locate it. Someone at the Catholic Answers’ forums found it. In the Declaration on Procured Abortion footnote 19:This declaration expressly leaves aside the question of the moment when the spiritual soul is infused. There is not a unanimous tradition on this point and authors are as yet in disagreement. For some it dates from the first instant; for others it could not at least precede nidation. It is not within the competence of science to decide between these views, because the existence of an immortal soul is not a question in its field. It is a philosophical problem from which our moral affirmation remains independent for two reasons: (1) supposing a belated animation, there is still nothing less than a human life, preparing for and calling for a soul in which the nature received from parents is completed, (2) on the other hand, it suffices that this presence of the soul be probable (and one can never prove the contrary) in order that the taking of life involve accepting the risk of killing a man, not only waiting for, but already in possession of his soul.So next time you get the Pope Sixtus-vs.-Gregory-in-a-steel-cage-death-match objection, shoot it down with this.–

Sorry, Scottgun, your answer is unclear, to me.

Are you then in favor of using the word “fertilization” or “conception?”

Well, that is what I’m concerned about. Namely, the rising movement of declaring pregnancy as beginning when the human implants.

So, I am worried that by using the word “conception” it could be used to show support for that political theory.

I think I am like you. Although I would not necessarily call it splitting hairs but rather concern with precision, I would agree that such a distinction would not get much traction in the overall argument. That is, “fertilization” vs. “conception” = dealer’s choice as it isn’t going to trump either way as you move on in the debate.

Word accuracy is important, but it’s also good to know your word history–as definitions and meanings change–and how that change fits with the rest of history.

Conception and fertilization used to mean the same thing. The formal change in the definition by the American College of Obstetrics and Gynecology came in 1965–a time when abortion was against the law in most of the US. Without that, abortion laws might have covered hormonal contraception. (Contraception was also against the law in some states until Griswold v Connecticut–also in 1965)

[FONT=Arial][size=2]In 1965, the American College of Obstetrics and Gynecology redefined conception[/size], saying, “Conception is the implantation of a fertilized ovum.” Previously, however, conception was universally defined in the scientific community as the fertilization of an ovum. The consequent redefinition of contraception has allowed the morning after pill to be labeled an “emergency contraceptive,” despite its potential to eliminate a fertilized ovum, a human being in its earliest stages of development.

Ironic, isn’t it, that due to a redefinition of a word now fertilization occurs before conception. In my high school textbook fertilization=conception. If conception were further redefined to equal birth+one month, it would really benefit those who don’t like what pops out of the birth canal. There would probably be a market for “preconception” organs. It would stimulate the economy. What other words could profitably be redefined?

Fertilization and Implantation are two specific terms for two different events. The term Conception is a general term. For Catholics Conception = Feritlization. Which I belive you also noted is the scientific definition.

Conception is the beginning of a new human life; this occurs at fertilization. From a medical standpoint, the individual has unique dna at fertilization. Whereas, at implantation, nothing occurs to change the individual per se. It is merely a change in location. The claim that conception begins at implantation is disingenuous.

No, science and medicine make that distinction because between 25% and 40% of all fertilized ovum fail to implant for whatever reason. This is why medicine defines pregnaency as beginning at implatation.

Which is also why the Church’s position that “life begins at conception”, if one equates fertilization with conception, doesn’t take proper account of science.

Implantation is the primary biological hurdle that the fertilized egg must surmount on its way to becoming a human being, although another 20% to 25% of implanted ovum (pregnancies) spontaneously miscarry for no discernible reason, often without the woman ever knowing she was pregnant.

You cross a line when you speak about “hurdles” that must be surmounted “on the way to becoming a human being.” All the DNA genetic material for a separate, unique human joins together when the father’s sperm joins the mother’s egg–aka fertilization.

If a fertilized human egg fails to implant for whatever reason, the fertilized egg was still a unique human with a father and mother. Early and untimely death does not change that. Many die at the fertilized egg or zygote stage, rather than advancing to other stages of human development such as the embryonic stage, the fetal, neo-natal, infant, toddler, adolescent, etc. etc.

People die at all stages of human development, but we should not define a human being based on age and location at the time of death. If a human dies before implanting that doesn’t mean he or she was not a human being–unless someone messes around with the definition of “human being”.

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