As long as we are talking bodily autonomy, would not autonomy begin with the very beginning of a body?
The fact that an unborn child at any stage cannot defend itself or speak for itself does not mean it does not have autonomy or rights.
Society as a whole is seen to have an obligation to defend a born child or adult who cannot speak for themselves or defend themselves -so why not more so an unborn child?
I would think women -who have had to fight to be heard and have say over their own bodies -should be more likely to think so.
You are asking a moral question, when this is a discussion about the need, legally, for the choice to be available to preserve a woman's bodily autonomy. Moreover, the bodily autonomy of the fetus is not at issue at all.
Bodily autonomy means a person has control over who or what uses their
body, for what, and for how long. Its why you can't be forced to donate blood, tissue, or organs. Even if you are dead. So, although the fetus is not legally considered a "person" with the rights that attach, even if it was, an abortion would not violate it. No one is trying to use the fetus' body to support another living thing. It is a one way street in this context.
The "right to live" for the fetus is not guaranteed BECAUSE of the woman's bodily autonomy. Morally, of course, I would agree, but morality cannot and should not be legislated. But, if you can explain how bodily autonomy would be violated for the fetus, I am all ears.