I am pro-choice. My reason is that nobody KNOWS at what point during development a fetus becomes a person. Science/medicine haven’t been able to answer that question definitively. Yes many people believe it is at the time of conception, but since that is just a belief, it amounts to a form of religion. Because those aspects of the fetus that a reasonable person would consider to indicate personhood (viability, physical developments, brain activity, etc) become increasingly evident over the course of development, I favor a sliding scale where restrictions on abortion increase over time in the womb.
Making abortion illegal in the first trimester thus, for example, seems to me a sort of religious decree, and not an appropriate legal mandate. It also has terrible personal and societal consequences.