Ethical implications of the mereology of pregnancy

It is often argued that in reproductive ethics, moral arguments rely on scientific facts of the matter, some controversial metaphysical assumptions and some crucial analogy. They usually take the form: given some scientific fact about fetuses or pregnancy and some metaphysical assumptions, pregnancy is analogous to some other scenario where some norm applies. If so, that norm should apply to pregnancy as well.Recently, Kingma proposed that, contrary to popular belief, the fetus is not merely contained by the gestator's body but a part of it. This is a metaphysical claim which is grounded by scientific facts of the matter. However, while this appears to have obvious relevance for reproductive ethics and has been acknowledged as such, it is not at all obvious how the metaphysics of pregnancy impacts ethical debates.I will argue that what is judged as analogous to pregnancy, and what norms therefore apply, will directly depend, to some extent, on the assumed mereology of pregnancy. However, I will also show that no particular position on any ethical question follows from any mereological view. So, in this paper, I propose that the mereology of pregnancy does not determine what you can argue for, but it does determine how you argue for it.