Separate issue, but all our “rights” is what we are willing to fight for that seem to be universal to the human experience that we would fight for. Such as right to bodily autonomy. Right to life, right to safe environments, rights to socialization, etc. Pick out any person anywhere at any time period and see how they react if you force them to give up their body’s use.
This isn’t an answer to the question. Is bodily autonomy something that humans
should have (a natural right), or just something that some people are
granted by society/government/what have you (an extrinsic privilege). If it is the latter then you have no grounds for arguing that the mother “should” have the right her own body, you can only say whether or not she is afforded this privilege by society. If it is the former then you must account for the other natural rights.
Let me put it this way: natural rights arise from the very nature of the thing in question. Natural human rights are inherent to human nature, and don’t require any law or consent in order to exist, though obviously these things are needed in order to support these rights (and must be fought for in many cases). Anything that requires consent to exist is not a right, but a privilege.
If bodily autonomy is a natural right, then it derives from human nature itself. Human nature itself is fundamentally dependent, at least in its early stages. If bodily autonomy is a right, then it follows that dependency is also a right since human nature is dependent in and of itself, not owing to outside accidents like injury, disease, or circumstance. A fetus isn’t dependent because it is a human that needs a womb, it is dependent because it is human; there is no human nature without this dependency.
If you deny this dependency, you deny humanity, and without humanity there are no natural human rights like bodily autonomy.
If you simply believe that these “rights” are merely the things people commonly fight for, then you don’t believe in rights but in privileges. Privileges that people universally fight for, but privileges none the less. It would be better to not speak of the “right of bodily autonomy” if that’s the case.