The Pro-choice Argument

An increasingly common pro-choice argument is to assert “consent to sex is not consent to pregnancy.” Generally, this slogan is a shorthand for a more comprehensive argument which implies:

  • Bodily autonomy is an absolute right in the sense that everyone has the right to refuse the use of their body to another person.
  • A woman must consent to pregnancy.
  • A pregnant mother can exercise bodily autonomy in the form of the right to refuse use of her body and revoke/withdraw consent to pregnancy via an abortion.

For this combination “consent plus right to refuse” argument to be valid, several underlying assumptions must be true:

  • Consent is relevant to the condition of pregnancy.
  • A preborn human is able to partake in a consent-based transaction.
  • Humans have no responsibility/liability for humans they have caused to be needy.
  • Abortion is merely denying use of your body.

The consent argument is sometimes followed with Judith Jarvis Thomson’s violinist scenario as proof that even if we acknowledge the personhood of the preborn human, the right to refuse use of your body is ­the key factor in determining the morality of the action of abortion (or, in her analogy, unhooking from the violinist).

The scenario, in a nutshell, is this: a world-famous violinist is dying. You get kidnapped and medically hooked up to the violinist to keep them alive. They will eventually be able to live on their own again, but if you unhook from them now, they will die. Should you still be able to unhook yourself from the violinist, even knowing they will die? Thompson argues, yes, you can, because you have the right to refuse the use of your body to anyone you want. If you do not consent to staying hooked up, you don’t have to stay hooked up. Then she ties it to abortion. If you do not consent to staying hooked up to your child, you may unhook from them, even if unhooking causes them to die. Your consent to the process of pregnancy and your right to refuse the use of your body are paramount to “reproductive rights” arguments.

Let us ignore for a moment two facts which many pro-choice people ignore anyways. First, Thomson’s violinist scenario/right to refuse argument has been answered very well by pro-life philosophers and lay people. Second, abortion is not merely refusing use of your body and letting someone die of whatever was killing them in the first place, but is actively and intentionally killing a gestating human in order to end the condition of pregnancy.

The purpose of this article is to challenge a different underlying assumption of the “consent to sex is not consent to pregnancy” catch-all argument; namely, that consent is relevant to the condition of pregnancy in the first place. I hope I can convincingly and logically show consent to sex is indeed not consent to pregnancy – because pregnancy is not a consentable action. And if consent to pregnancy cannot be given, then it cannot be revoked or withdrawn via an abortion, and justification for abortion must come from a different argument than right to refuse or revoking consent to pregnancy.

What is Consent?

To determine if consent is applicable to pregnancy (or any situation), we must know what consent even means. Consent is not merely assenting to something, though consent and assent are very often conflated. Assent is a mere agreement or demonstration of approval, and may be made to no one, or to oneself, or to anyone about anything. Assent has no basis in social contract, no requirements for the parties involved or the action, and has no transformative power. However, consent has all these qualities. A very basic definition of consent follows:

“Consent is a three-place transaction in which consent to do something—φ—is always given to another party or agent, to whom we will refer as B.” (1)

That is, consent is a transaction between two parties. One party (A) gives it, the other party (B) receives it. 

[From here on out, I will refer to the giver of consent, A, as Alex and the receiver of consent, B, as Bob]

Bob may have asked Alex for consent to perform an action, or Alex may have preemptively approached Bob about an action and given consent for Bob to do it (like choosing a plumber to install a new water heater). It is also possible that Bob may be asking Alex to perform the action but A must still give consent (like Bob asking Alex for a favor). In any case, consent must be given from one person to another. Consent does not mean Alex merely assents to φ happening, but properly understood, Alex gives consent to Bob to do or perform an action φ.

Consent is also not merely internal to Alex. There is more than a mental or emotional component to consent. Consent must have a communicative and expressive component, because consent is meant to transform the moral relationship between two persons. Consent is a social contract of sorts. In order for Bob to know they have consent to do something – whether that is driving their parents’ car or having sex with their significant other –Alex must have somehow communicated their consent to Bob, and in a way which Bob can understand. This aspect of consent is recognized readily in many cultures by requiring signatures on contracts, requiring verbal and/or written (and informed) consent to medical procedures, encouraging obtainment of a verbal, enthusiastic “yes” from your sexual partner before intercourse, or otherwise making sure there is a mutual agreement, etc.

So, when is consent applicable to any given situation? For consent to logically be applied, certain things need to be true of the giver of consent (A, Alex), the receiver of consent (B, Bob), and the action Alex is giving consent for Bob to do (or to do for Bob) (φ).

Requirements for the giver of consent (A, Alex)

To start with, Alex must have some level of biological and mental maturity or cognitive ability which allows for an understanding of the situation and action in question. Alex needs to understand what the action is they are giving consent for another person to do.

Most people would also agree Alex deserves to be informed or have access to resources to get information about the possible outcomes, side effects, risks, consequences, and/or natural results of consenting to an action being done by Bob. That is, some understanding of the natural or possible consequences of the action is required for the consent to be meaningful and valid. This is usually referred to as informed consent. While this term is used heavily in the medical field to describe the sort of consent required for a medical professional to gain from a patient prior to performing a medical procedure, it is used in other situations as well, though it may not necessarily be called “informed consent.” 

Alex must also give consent freely (not be coerced, forced, threatened, etc.) and intentionally (conscious, sober, etc.).

When all these conditions are satisfied — competence, freedom, and intentionality —  Alex is able to give consent to Bob to do φ. This also means Alex is responsible, at least partially, for the outcomes of φ. Giving informed consent may require the consenting party to agree to not hold the receiver of consent and performer of the action liable for the outcome of the action. That is, whatever the outcome is, the consenting person agrees to the general responsibility and/or legal liability for that outcome.

This could even be seen legally in certain contracts, medical forms, and simple parental permission slips for school activities, to name a few examples. We also see the responsibility aspect of consent in any law which has age of the person as a factor for prosecution of a crime they committed. To put it another way,

“If A cannot be held responsible for what gives the appearance of consent, then consent has not been given.” (2)

Furthermore, we could look at an example involving sexual activity to see how Alex might fulfill the requirements for being able to give consent. The purpose (or one of the purposes) of sex education is to help people give informed consent to sexual activity. Since they now presumably know the possible risks and natural consequences of various forms of sexual activity, they can weigh those outcomes against the benefits of the action and make an informed decision about giving or withholding consent concerning their sexual activity with another person.

If Alex and Bob are both sober adults, and Bob tells Alex they have genital herpes before Alex gives voluntary and intentional consent to Bob for sexual intercourse, then Alex has made an informed decision to continue sexual intercourse even though they risk contracting a herpes simplex virus by doing so. If Alex finds out they did indeed contract the virus, they must take responsibility for that outcome on themselves, such as choosing to seek treatment or letting future sexual partners know they are contagious; Bob cannot and should not be held liable for Alex’s contracting the virus.

Requirements for the receiver of consent (B, Bob)

While Alex needs to have a high enough level of cognitive ability to give (informed) consent for Bob to do φ, Bob must also be able to understand the situation enough to receive consent from Alex. Remember, consent is a process which actually transforms the moral relationship between Alex and Bob. Therefore, Alex must not only somehow communicate their consent to Bob, but Bob must also be able to understand that communication.

If Alex owns a car and verbally gives consent to Bob to drive their car on a certain day, but does it while Bob is sleeping and cannot hear them, and makes no attempt to wake Bob up, then the consent is meaningless. How is Bob to know they can use the car that day? Bob never actually received the consent of Alex, although Alex may try to claim they gave it. Therefore, with Bob clueless to the consent given, the moral relationship between Alex and Bob remains unchanged.

Requirements for the action being done (φ)

When considering φ, the action Alex is giving consent to Bob to do (or giving consent to do for Bob), it must be an action that Bob is not morally permitted to do to Alex or with Alex’s stuff without Alex’s consent. Or it might be an action which Bob has no moral grounds to demand of Alex.

For example, Alex and Bob are friends. While out together, Bob drops and breaks their phone. Bob later asks Alex permission to use their phone to get an Uber, since Alex’s phone is still intact and functional. Although friends, Bob has no moral grounds to demand the use of Alex’s personal property or to otherwise use it without Alex’s knowledge. Alex must give consent to Bob for the use of their phone.

If Bob already has a moral entitlement to an action, Bob does not need to receive consent from Alex (though sometimes even in these cases it is nice for Bob to ask permission, just to be polite). If two people are legal co-owners of a car, either person has the moral and legal right to use the car at any time. However, for the sake of kindness, it would be nice if both people made sure their individual use of the car at any given time did not leave the other owner stranded somewhere without transportation.

The action also needs to be one which Alex has the authority to consent to Bob doing, both morally and legally. If Alex is part of a gang and wants to have someone killed, it does not matter if Alex gives consent to Bob to go kill Carl. That is not a decision Alex can make morally, because the consent given to Bob to do that action would impose harm upon and violate the rights of Carl.

The action may also be either conclusive or ongoing. In cases where the action is ongoing, it is also reasonable to say consent can be withdrawn along the way, though not always without penalty or liability. Since giving consent alters the moral relations between Alex Bob and often creates a reliance of Bob on Alex, withdrawing consent could seriously disadvantage Bob, and Alex may be reasonably expected in some cases to be liable for the results of withdrawn consent.

For example, suppose Alex and Bob mutually agree to a carpool schedule. Bob was the one who needs the ride and offers to pay Alex gas money if Alex picks Bob up every day for work. Alex gives consent to Bob for this carpool setup. They do this for a number of weeks without incident until Bob comes to expect Alex to pick them up. Then one day, Alex decides they do not want to pick up Bob anymore, and they have decided this without giving any prior notice to Bob.

Technically, Alex can withdraw their consent to picking up and driving Bob at any time. However, a history of ongoing consent has created a reliance of Bob on Alex, and withdrawing consent now seriously disadvantages Bob, who now may be late for work or even unable to get to work at all, which could mean repercussions from Bob’s employer. It would be reasonable in this situation for Bob to expect Alex to be at least partially responsible for the consequences of their withdrawn consent, such as by arranging another mode of transportation for Bob at least for the day Alex withdrew their consent without notice.

What activities never require consent because they cannot be given consent for?

There are some actions, processes, and occurrences which never require consent because they do not come under the basic definition of consent or fulfill the requirements for AB, and φ. These are:

  • Any natural biological, chemical, or physical process
  • A consequence, risk, outcome, etc. of an action
  • An action, happening, process, etc. which neither A nor B has any direct control over

For example, you do not consent to digesting your food. In this case, to who, are you giving consent? Your own body? You can make the decision to eat or drink something, an action which you have control over but to which consent still does not apply, with the knowledge that digestion will be the natural biological outcome of your action. But that is merely assenting to digestion happening, not giving consent to someone to perform or do an action. You also have no direct control over your digestion — it will happen whether you want it to or not (unless you die shortly after eating or have something wrong physiologically).

Likewise, none of the automatic physiological processes your body performs require consent — breathing, heart beating, kidneys filtering blood, production of ATP by the mitochondria, etc.

While that example covers the first and third category of non-consentable actions and processes, what about that second category: A consequence, risk, outcome, etc. of an action?

Let me pause to ensure everyone right now: I am not arguing that when someone gives consent to someone else to do an action, the giver of consent is then “off the hook” for what occurs as a natural consequence of that action. As discussed earlier, true consent is informed (or where informed consent was not obtained, Alex at least had information readily available to them which they are then held responsible for), therefore Alex can be liable or responsible for the outcomes of the action. However, an outcome of an action is not something which can be consented to.

Remember, consent involves Alex giving consent to Bob to do an action, φ; consent does not directly apply to outcomes from φ. As mentioned earlier, Alex can give consent to Bob to have sex with them, and Alex getting an STD/STI from Bob may be a natural consequence of that action, but the actual contraction of the STD/STI cannot be consented to.

Or, when a patient gives their informed consent to a hospital’s staff to perform an operation to remove a cancerous growth from an organ, this is not consent to any outcome, whether positive or negative. The outcome — not having cancer or still having cancer — is not something which can be consented to.

Most of these definitions and conditions are aspects of consent we already use and intuitively know. However, many times people cannot articulate what they mean when they say “consent.” When asked to define consent and under what conditions it may occur, many people either do not have an answer or come up with something which sounds a lot more like assenting to an action or outcome rather than giving consent to a person to perform an action.

Can Pregnancy Be Consented To?

Let us look at consent in the specific case of pregnancy and abortion. Can a person consent to the physiological process of pregnancy? I argue they cannot.

First of all, I am going to nitpick a bit here and state that the phrase “consent to” something is really not the correct (formal) terminology to be using. You give consent to someone to do an action.

Many pro-choice people get hung up right here. They insist you consent to an action happening. But that is absolutely not the proper understanding of consent. You can assent to an action happening, but consent always involves at least two people in a transaction which transforms their moral relationship. If the idea of consent only meant you agreed to certain actions happening to you, it would not matter who does the action. You do not actually just consent to sex. This would mean you merely assented to the act of sex happening to you, no matter who else was involved. You give consent to a specific person to perform the act of sex with you. The whole slogan “consent to sex is not consent to pregnancy” is sloppily written. It may be catchy, but it does not portray consent accurately.

However, if you ask a pro-choice person to whom the pregnant woman is giving consent for her pregnancy, you may then hear a response like, “the woman must give consent to the preborn human growing in her body for them to remain in her body.” However, the preborn human cannot receive consent. They have no concept of permission, consent, intentionality, or deliberate action. They do not understand verbal or written language, gestures, body language, looks, or touches. There is no way for a woman to communicate consent to her preborn child in a way the preborn child will understand. Just like consent cannot be given to an unconscious adult human (or come from such human), consent cannot be properly applied to any situation, including pregnancy, until the receiver of consent can understand what is going on.

Beyond not being able to give consent to a human embryo or fetus, perhaps more important to keep in mind is that pregnancy (or the state of being pregnant) itself is a natural physiological process and an outcome of an action. It is a complex chemical and biological symbiotic relationship between the developing human and the mother. Pregnancy, or the state of being pregnant, is itself not a person, but a process, and as such, the process of pregnancy can at no point receive consent because as we have stated earlier, only persons with the capacity to understand consent can receive it.

Again, to whom would the woman be giving consent? Certainly not to the growing human inside her! To her own egg to fuse with a sperm? To her own uterus to accept an embryo? To her own body to continue sheltering and giving sustenance to the child? The idea of a woman being able to give her consent to the process of fertilization, implantation, and gestation is ludicrous. They are mere processes, not persons; and moreover, they are processes which neither the woman nor any other person has direct control over (if we did, IVF clinics would have near-100% success rates!). Just as you do not give consent to your own heart to keep beating, your own lungs to keep breathing, or your own hemoglobin to carry oxygen through your bloodstream, a woman cannot give consent to individual parts of her own body involved in the process of bringing a new human life into existence and keeping that human safe and fed until birth.

There is really no way around it. In no understanding of the framework of consent could we ever logically say pregnancy itself can be consented to. Only for the act of sex (or, say, IVF procedures) could consent be given; resulting outcomes from those actions cannot be given consent for.

Other Considerations Concerning Consent, Pregnancy, and Abortion

Because pregnancy is a reasonably foreseeable natural consequence of sexual intercourse, and assuming Alex and Bob both know the basics of the birds and the bees, then pregnancy is an outcome of an action for which the people involved in the action should be reasonably expected to take responsibility or be liable.

It is morally bankrupt to posit that the new living human organism which resulted from an informed decision can be killed as a way to take responsibility for the outcome of said decision. In fact, to be responsible and liable for the newly created, inherently needy human, you could make a strong argument in favor of gestation at least until ex-utero viability, and then live delivery (this is known as evictionism).

Additionally, consent is only needed when Bob has no moral authority to perform an action or demand an action from Alex. In the case of pregnancy, a pro-choice person would need to prove the preborn human even needs consent from the mother to come into existence, implant, and grow. This seems obvious to many pro-choice people. Of course, any person using another person’s body needs their consent to use it! But they ignore several key factors in the very special case of pregnancy. How does a preborn human ask for or receive consent? They can’t. They had absolutely no say in their circumstances, either. They were the product of an act which by its very nature has the possibility of creating a needy human life. The child did not cause themselves to exist in their mother.

To say effectively, “Too bad, I don’t care if my actions put you in the circumstance you are in, I’m still going to kill you for using my body,” sounds an awful lot like entrapment. If you trap a person somewhere and they have no way of leaving without harming themselves or come to harm while trapped, you are, to some extent, responsible for the harm which befalls them. This can even be enforced legally.

We can also look at the extreme but logical implications if consent did apply to pregnancy. The implications would go against our moral intuitions and serve to show it is utterly illogical to say pregnancy can be consented to. This is not surprising, since many pro-choice arguments necessitate extreme views (not to say that pro-choice people themselves are extremists, just that some of their reasoning has extreme logical conclusions). If pregnancy requires consent to be given to the human fetus from the mother, and this consent must be active, ongoing, and can be revoked or withdrawn at any time, then any time the mother is not actively giving her consent to the fetus, the fetus is assaulting the mother. This introduces a whole host of outcomes which are quite unsavory to any rational person and go against all our moral intuitions. Can a human embryo or fetus really be held accountable for their “actions” which they have no control over? The implications of pregnancy actually being a consentable action are explored more in-depth in this article.


It is clear pregnancy is not something which can be consented to and a human embryo or fetus is not someone who can receive or ask for consent. Therefore, abortion cannot be described as revoking or withdrawing consent to pregnancy. Additionally, one cannot justify abortion as a moral or ethical means of taking responsibility for the action which was “consented to” with the knowledge that a possible natural outcome is the creation of an inherently needy human.

Here’s a handy chart you can use in a pinch when you don’t know if consent applies to a situation or not:


  1. The Ethics of Consent: Theory and Practice, Franklin Miller and Alan Wertheimer2009, pg 5
  2. Ibid. pg 13

Further Reading/Listening:

The Ethics of Consent: Theory and Practice, Franklin Miller and Alan Wertheimer – while I only quoted it a couple of times, this text substantially helped me in forming the definition of and parameters for consent outlined in this article.

Equal Rights Institute did a fabulous job tackling this specific pro-choice argument in a much less academic and perhaps more intuitive way in this excellent article and in this amazing podcast episode. I’d encourage anyone to listen to the whole episode, but if you skip straight to 18:40 you’ll see how Rachel says the same thing I am saying in a different way.

Tort law discussion – taking responsibility for the reasonably foreseeable outcome of an action, whether the outcome was inteneded or not.

Website | + posts

I love science and teaching. I am passionate about using those interests to speak for those who can't.

The views and opinions expressed in these articles are those of the author and do not necessarily reflect the official position of Human Defense Initiative.