When I see people whining about women spreading their legs without also berating men to keep their pants zipped I see a half solution.
Men are able to be continent as well as women.
Men solve their part of this dilemma by walking away and leaving the woman with the baby.
In that situation the man has no problem, nor is there any penalty for him for not keeping his pants zipped. These men are always going to vanish into the night after they get what they want and the consequences show up.
It is not within anyone’s power to make sure there are no men like this; They are always going to be out there. It is within the woman’s power to make sure she doesn’t allow a man like this to get her pregnant.