I think it can help to look at what most people can agree on - infanticide is worse than late term abortion, which is worse than early abortion, which is worse than the morning after pill, which is worse than condoms or other contraceptives. Wherever you draw the line and say that this should not be allowed, no woman actually wants to bring a foetus to term, give birth and then kill her child. Nobody wants to have a late term abortion rather than an early one. Nobody would rather abort a foetus than stop conception from happening at all.
If it’s framed as a slippery slope argument, this is completely misrepresenting what the pressure from the different sides is actually doing. Not supporting comprehensive sex education, contraceptives and the morning after pill, then putting financial and logistical barriers in the way of access to abortion pushes everything back, making it more likely that the foetus will be at a later stage of development or maybe forcing a woman to bring a child into a very unsuitable situation. It can also put women in danger if they try risky procedures when they can’t get proper care, and can place excessive burdens on families when more choice would have allowed them to care for the children they have (or not to have them at all).
While infanticide and abandonment are very real, where I’ve seen it it’s generally been due to an extreme lack of choice and desperation on the part of the mother (or more often pressure from others). Giving women choices and power at every stage can be hard to accept for people who see abortion at any stage as killing a person, but I think it can be justified even under that perspective.
ETA: this is the one sticking point that would keep my wife from voting Bernie Sanders. I don’t think she’s alone in this and I hope that finding ways of reframing the debate will convince a number of evangelicals to abandon the “pro life” party in favour of a candidate who is a lot more representative of their views.
