Basically, I have previously had similar thoughts but (unfortunately) didn't articulate them as clearly as I am currently doing. Indeed, here goes:

(For the record, I consider the "bodily autonomy" argument to be an intellectually lazy argument; plus, even I don't believe that bodily autonomy should be some kind of "holy cow.")

Since it is not the pregnant woman's fault that her embryo/fetus is unable to survive without the use of this pregnant woman's body (rather, this is the fault of biology), the pregnant woman certainly shouldn't be legally required to allow her embryo/fetus to continue using her body.

Indeed, the only thing that a pregnant woman is responsible for is the existence for this embryo/fetus. However, causing someone to exist certainly shouldn't justify being required to provide additional assistance to this person (such as by being required to allow this person to use one's body). After all, this is similar to saying that if I extend someone's life by giving this person one of my kidneys, I should also be legally required to donate, say, blood or bone marrow to this person at some later point in time if this person will (as a result of biology) develop additional health problems and will need my blood or bone marrow in order to survive. Indeed, I simply caused this person to continue existing--I certainly did not cause this person to develop a need for a blood donation or for a bone marrow donation.

Also, in regards to the "throwing a person off of your boat" scenario, even if I accepted the premise that a boat can be compared with one's body, there is a relevant difference between this scenario and pregnancy. Indeed, if you invite someone (as in, someone who cannot swim) onto your boat and then change your mind and want to throw this person overboard, you certainly shouldn't (legally) be able to do this because it is your fault that this person cannot be removed from your boat without dying afterwards; after all, had you not sailed out to sea (and would have rather kept your boat anchored on land), you would have been able to remove this person from your boat without causing this person to die afterwards (after all, a person who cannot swim can certainly survive on land).

In contrast, there is never any way for a pregnant woman to remove an embryo/fetus from her body which doesn't result in the death of this embryo/fetus afterwards. Thus, pregnancy simply isn't comparable to inviting someone who cannot swim onto your boat.

Anyway, any thoughts this argument of mine and on everything that I wrote here?