Ectopic Pregnancy vs Parasitic Twin?


So I’ve been browsing the forums for a little bit today, and I noticed something a little head-scratching…

I’ll start with the disclaimer that I’m definitely pro-life, so this is not meant to be an argument in favor of abortion.

My search started with a look into the ways of treating ectopic pregnancies - dangerous situations in which the fetus implants into something other than the uterus lining, most commonly the fallopian tubes. The Church’s position seems to be: you can’t just take out the child, because that would be direct killing, but taking out the tube with the child in it and allowing it to indirectly die would be the moral route to take. This comes off a bit like a technicality, but the argument seems legit. I’ll take it.

However, I then came across this thread about parasitic twin situations:
Here, it seems the people on this forum agree that it’s perfectly fine to remove a parasitic twin from the sibling even though it will die as a result. I mean, a parasitic twin is an innocent human being as well, right? So shouldn’t it be given the same treatment as an unborn child? A quote from the thread reads:

Of course there is nothing wrong with seperating two humans when their lives are in danger so long as one does what they can to keep both alive. This has always been Catholic teaching.

So what’s the deal here? Why is removing a parasitic twin moral while removing the ectopic child is immoral? Both are situations where two human beings are at risk of death unless they’re separated from each other.




What do you mean by “remove”? Removing the connection between the two and letting nature take its course is much different than taking apart a living human person limb by limb. The person’s death should not be the means of rectifying the problem but rather the unintended (and perhaps inevitable) consequence of the removal.


What you stated about ectopic pregnancies if generally understood to be church teaching, but the church has no official teaching on ectopic pregnancies. So the best decision, in each case (ectopic or parasitic twin) would be lots of prayer and advice from one’s pastor under the counsel of one’s doctors.

I personally don’t quite buy that the portion of tube must be removed as well for it to be a licit action, because the tube is not always damaged in the process, otherwise the pill taken to treat the mother/end the pregnancy would not be effective. There are so many variables that it really is a case by case basis.


The parasitic twin is a tumor and not an innocent human life. Removing it is no more immoral than removing any other tumor from the body.


The article I linked from the National Catholic Bioethics Center says:

“Another morally problematic technique involves cutting along the length of the fallopian tube where the child is embedded and “scooping out” the living body of the child, who dies shortly thereafter. The tube can then be sutured back up. This approach, like the use of methotrexate, leaves the fallopian tube largely intact for possible future pregnancies, but also raises obvious moral objections because it likewise directly causes the death of the child.” [emphasis mine]

I suppose the term “scooping” could refer to a procedure that directly injures the child during removal, but the article does seem to balk at the idea of separating the child from its mother directly at all, favoring instead removing the “damaged tissue” with the child in it. I personally think that simply severing the child’s connection to the fallopian tube would fall under the category of “not directly killing but death as practically inevitable consequence,” but this is the issue I’d love to discuss.

I don’t know if we can be too sure about that. If I can quote Wikipedia…

“A parasitic twin (also known as an asymmetrical or unequal conjoined twin) is the result of the processes that produce vanishing twins and conjoined twins… Parasitic twins occur when a twin embryo begins developing in utero, but the pair does not fully separate, and one embryo maintains dominant development at the expense of the other. Unlike conjoined twins, one ceases development during gestation and is vestigial to a mostly fully formed, otherwise healthy individual twin.”

So from what I understand, a parasitic twin is basically a conjoined twin that didn’t happen to get enough of the biological pie to develop beyond a certain point, hence the alternate title “unequal conjoined twin.” I doubt that we would consider regular conjoined twins to be anything other than two separate human souls in an unfortunate circumstance… And the only difference in the case of a parasitic twin is that it doesn’t develop properly or far enough. And we all know level of development does not determine human dignity, right? :slight_smile:

I understand that in a lot of cases the parasitic twin is just dead, so of course it would be fine to remove that, but the wide range of weirdness that goes into determining where the healthy twin’s body ends and a separate being’s body begins (or whether it’s a separate being at all) is enough to drive me mad. And if we can’t possibly KNOW for sure, then there is a CHANCE that we’re dealing with a living human being.

In a way it’s comforting to know that the Church doesn’t have a formal teaching about these complicated occurrences, because it makes for absolutely fascinating discussion.


What exactly does the Church teach regarding abortion if the mother’s life is in danger? Or if the child is a product of rape or incest? :confused: I’m pro-life but I wasn’t sure what the Church teaches about those more complex situations. And sorry I just added another question instead of helping to answer.


To put it simply we can never commit an intrinsically evil act for a greater good. So in the case of a complication of a pregnancy, we can never commit an evil (killing of the child) for the good of saving the mother’s life. However, there can be morally justifiable actions if the mother’s life is in danger due to pregnancy. The simplest example is the ectopic pregnancy. We cannot directly kill the child and remove the child from the fallopian tube (that is murder, can’t argue against that). However we can cut out the fallopian tube containing the child, and the death of the child is the unintended consequence of trying to save the mother from the ectopic pregnancy. It’s morally justifiable because the cutting out of the fallopian tube is a morally neutral act, it just so happens that it results in the death of a fetus. However, the direct killing of the fetus in an ectopic pregnancy is not acceptable because the action is objectively murder.
In the case of rape or incest, abortion is never allowed. Abortion in every circumstance is never supported because like I said before, no one can do an intrinsically evil act (killing infant directly) to bring about a greater good. So abortion is never allowed in any circumstance. In the case of rape, this is especially not acceptable because even if a person did not want to have a child, it does not give the person the right to choose to take the life of the child. Apply this to a person suddenly in custody of a child he/she did not want from forced adoption (hypothetical situation). Just like an unwanted pregnancy from rape, the guardian has no right to take away the life of the child just because he/she does not want to have the child.


I just don’t agree with the CC on this matter. Yep, you’ve got two lives here–mother’s and child’s–and sadly, you can only save one. The poor baby isn’t going to make it, period, so you need to kill the baby and remove it to protect the mother. What a tragedy, and how heartbreaking for the parents, but not intrinsically evil. HOW you kill the baby just doesn’t seem to me to make much of a difference–whether by methotrexate, or by surgical removal of part of the tube.

If you’re arguing about intent–well, the parents in such a situation usually don’t WANT to hurt their child; their desire is for the pregnancy to continue and the baby to be born alive and healthy. Alas, this cannot be, so their desire is to protect the mother, which seems to me to be a very good object.


The problem is that by saying “the poor baby isn’t going to make it, period” doesn’t really help the argument that there is objective truth and objectively moral actions and immoral actions. A different person can make the argument that “person A is gonna die anyway so whatever happens doesn’t matter.” It’s somewhat like a utilitarianist view of the world, which the church rejects because the action taken, not just the result, is important in determining whether it is a moral action or not. For example, if a person is gonna die soon from natural causes, it doesn’t make it moral to kill that person intentionally right before his natural death just because the person was going to die anyway. Killing a human being is objectively wrong no matter what the circumstance. And your last sentence, it is a very good object, however we can never commit intrinsically evil actions for the intention of achieving a good. The ends do not justify the means. If that were the case, then we can wipe out half the world’s population to end world hunger for the “greater good” and since they were all gonna die anyway.

Hopefully we can end it here and just agree to disagree since this doesn’t really directly answer the question from the OP. And I’m no moral theologian (just spending too much time on the internet).


[quote=Kmon23;12133214 Killing a human being is objectively wrong no matter what the circumstance. And your last sentence, it is a very good object, however we can never commit intrinsically evil actions for the intention of achieving a good. The ends do not justify the means. If that were the case, then we can wipe out half the world’s population to end world hunger for the “greater good” and since they were all gonna die anyway.

Sorry, I can’t resist responding; “Killing a human being” is not always objectively wrong–just most of the time. There are times in the Bible when God commands the killing of human beings.

I reject “the ends justify the means,” but the fact is, whether you just remove the tube or administer methotrexate, you’re actually going for the same end–which is to prevent the mother’s death–and you’re employing the same means–removing the embryo that is the source of the problem.

Now, if you want to agree to disagree, we can leave it, if you like!


I’ll respond once :D. Now two points.
You said that there are times in the Bible when God commands the killing of human beings. This is of course not objectively wrong because God has every right to take back life He has given. It is that he employs the usage of human armies/soldiers for that purpose. However, the reason why killing an innocent person is evil for us is because we as humans have no right to take another’s life. God can take life. We can’t, hence it is an evil act to my knowledge for a human to do so of his own volition. It explains why it’s in the Ten Commandments for humans to follow.

In the second point, it is true that both are for the same ends, however most Catholic moral theologians would disagree that the doctor is employing the same means. Directly killing and an unintended consequence of the death of the fetus are two different things. This is why abortion is never condoned in Catholicism because the dismembering of a fetus is a direct killing of an innocent being which is listed as something we should not do in the Ten Commandments. Now this last point is something pro-choice advocates may disagree on but it is how Catholicism teaches this matter, especially under the principle of the double effect.

Okay, now I’m done. Back to the OP


This USCCB document answers your questions:

Ethical and Religious Directives for Catholic Health Care Services
Part Four: Issues in Care for the Beginning of Life

The mother’s life is “at risk” but it is not guaranteed. An abortion guarantees the death of the child. The church prefers to accept the risk and work to save both mother and child.

There is no rape and incest exception. The child is innocent. In rape the mother is also innocent. If the child is unwanted, there are thousands of infertile couples who are waiting to receive a child they can call their own.


I think they are simply speaking of separating the twins, and that one is very likely to die. And in the case of “parasitic twins” one of the twins is usually only partly developed and even without a heart or brain. So a parasitic twin may simply be the arms and partial torso of what was going to be a twin.

There are cases when con-joined twins share a heart and lungs, or the liver and kidneys, having just one set of organs for the two to use. This is different than a parasitic twin in my understanding, but I think the same process is in progress when this happens. Division is incomplete or there is partial re-absorption of the twin by the other.

It has been a long time since I studied this stuff, so your post has encouraged me to look into this more. I really do think that they are speaking of twins that cannot survive and the presence of which may actual endanger the other. (Partial and incomplete formation and not truly living.)


Ectopic Pregnancy and Parasitic twins are two topics that require compassion and love. They are different topics which means we should not put one verses the other but rather we need to look at each situation carefully and without judgement. Granted both result in the unfortunate death of someone but we need to look at it in medical and ethical terms.

The first ectopic pregnancy: the reason why doctors decide to terminate the pregnancy is because there are women who have died from allowing the pregnancy to continue. It is that simple. Furthermore, biologically fallopian tubs are not meant for babies to grow. There is a reason why women have uteruses to carry their children. When a baby grows in an area that is not the uterus, it causes great concern and depending on the location where the tiny zygote implants itself it could put the women’s life at risk. Every now and then we hear of cases where ectopic pregnancies went undetected until after the fetus was past its first trimester. When this happens, the women are admitted into the hospital until the baby can safely be delivered by c-section. Due to their location, often these children are born prematurely which causes other problems. Often it is asked who has the right to live the mother or the fetus? In this case if the fetus is allowed to mature, it is putting it’s mother’s life at risk and for safety concerns, doctors decide to terminate the pregnancy in order to preserve the mother’s life.

In terms of the parasitic twin- you have to look at it case by case. In most cases, these parasitic twins are connected to their twins but they do not have the organs necessary for live to flourish. For example many parasitic twins don’t have heads or brains which allows basic functions to occur. Instead, they have extra limbs which are connected to their twins in such a way that if they are not removed it will kill their live twin because these extra limbs put a strain on the heart. These parasitic twins are only kept alive by being connected to their live twins. Most have no heads, nor an ability to make decisions therefore if they are removed there is no way they could survive so that their twin can survive so be it.

Sometimes we have to trust doctor’s decisions because they know how god created our bodies.


No one seems to have considered the excellent question raised by…

It seems to me that the injunction against doing evil so that good may come of it only clearly applies to the use of methotrexate to kill the baby. It is wrong because the death of the baby is absolutely necessary to the success of the operation. If the baby doesn’t die, the operation has failed, and the problem in the fallopian tube remains.

But the surgical procedure of slitting the fallopian tube and removing the baby, while it may directly kill the baby just the same, is not relying on the death of the baby to accomplish the cure. If somehow the baby did not die, the operation would still be a success. So it seems to me that this is not a case of doing evil so that good may come of it. It is a case of an unintended, but maybe unavoidable, consequence.

Currently, medical technology is not able to remove such a baby and keep it alive some other way. But there is no reason in principle why this might some day be accomplished. So for the slit and remove procedure, we have these points:

  1. Keeping the fallopian tube functional is a practical possibility and a practical advantage.

  2. This is not an instance of doing evil so that good may come of it.

  3. This procedure does not offer any worse practical chances for the baby than the section removal procedure.

I can see no moral reason to prefer the section removal procedure, especially if future developments in medical technology improve the prognosis for full fallopian tube functionality, and possibly even a way to keep the baby alive to fully develop.


Exactly this ^^^^

closed #18

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