That's part of the logic (basically overriding the definition of statutory rape to be "not rape" if the underage child enjoyed it)

But there are a bunch of similar decisions here: https://scholarship.law.upenn.edu/cgi/viewcontent.cgi?articl...

And the common theme is just because the parent is raped, doesn't override the rights of the child.

It's easy to see how that logic would be extended from child support to abortion.