I have seen that argued a lot, but it doesn't hold up to any scrutiny for the general group that claim to hold these views[0]. If that was the case, they would be working to make condoms and BC, especially semi-permanent BC like IUDs, much more widely available and they would work hard (they are trying to save lives here) to ensure excellent sex education. There also wouldn't be exceptions for women who had been raped (terrible fate, but the kid shouldn't be killed for it).

If on the other hand this is about punishing women for having sex, then they would try to prevent access to BC, as it removes the risk of pregnancy, and would have exemption for women who were raped because they didn't do anything worth punishing.

Of course I haven't seen anybody who is against abortions arguing that we should make spare kidney donations mandatory, despite the fact that people (who are, without a doubt, people) die waiting for a transplant. If you are not willing to make that argument, I don't see how you can logically argue against abortion.

[0]: I am not claiming that some individuals don't hold that belief.