Why the pro-choice movement is losing?

I think one reason is they typically just aren't very good at persuasion. Here's Ann Furedi attempting to argue there should be no limits on abortion.

What we have to ask ourselves is whether there needs to be any policy intervention or social intervention to change or regulate what is going on at the moment. And I don't think there does. There is no evidence to suggest that we need to restrict later abortions in any way, by enforcing legal time limits. And I certainly don't see any reason to think that doctors are abusing the current situation, or indeed that women are abusing the current situation......

Does late abortion have a detrimental effect on society? No, I really don't think it does. There is no evidence that the number of women requesting late abortions is increasing. The figures remain very much the same. However, does the idea that we can override who makes these decisions about late abortion have a detrimental effect on society? Yes, I really believe it does. Because what we're really saying when we argue that an earlier time limit needs to be imposed is that we don't trust women's decisions, and we don't trust doctor's decisions.

Notice the complete lack of evidence and thoughtfulness. Furedi's reasons for why something should be or shouldn't are as follows: "I don't think there does", "I certainly don't see any reason to think", "I really don't think it does" and "I really believe it does."

It's like the end all and be all of evidence for Ann Furedi is what she believes.

This is how elementary school children argue. Yet she's one of (if not the) leading voice for abortion in the UK.