I'm not big on the overall lore, but yeah, I'm pretty sure all mages of note are sterile. And this would probably help play into how she feels about Ciri, being the lover of the man trying to be a father figure to her would naturally lead Yen into being a motherly figure towards Ciri.
I didn't see season 2, but wasn't her whole persona that she was beautiful and powerful, but sacrificed her ability to have children and regretted it?
If they dropped that, what was her character's point/motivation?
I'm not big on the overall lore, but yeah, I'm pretty sure all mages of note are sterile. And this would probably help play into how she feels about Ciri, being the lover of the man trying to be a father figure to her would naturally lead Yen into being a motherly figure towards Ciri.