She would eat less due to discomfort but never completely stop and would always take treats...
I would guess your hen isn't eating because of whatever is going on with her reproductive system. For whatever reason issues laying can really put a hen off food. I might try torpedo feeding (
https://www.backyardchickens.com/th...eeding-what-is-it-and-when-to-use-it.1532744/) to keep her strength up while she hopefully recovers and get her appetite back. You could also look into natural remedies like acv water or a little bit of garlic to help her appetite.