Any good faith reading of the Thirteenth Amendment leads to the conclusion that whatever rights a fetus may or may not have, it does not have any property rights to the uterus in which it resides. The Thirteenth Amendment explicitly abolishes the practice of granting property rights in a person’s body to anyone or anything other than that person.
I really wish that the legal arguments in favor of abortion had been properly framed. The right to privacy is entirely the wrong way to look at it. A woman’s uterus is nobody’s property but her own; to argue otherwise is to promote slavery. It’s easy to see exactly how ridiculous arguments about fetal rights and fetal personhood are once you adopt the belief that women are not slaves.
Appendix: The Thirteenth Amendment:
Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction.
Congress shall have power to enforce this article by appropriate legislation.
Appendix 2: the document itself.