I don't remember much of the fic but I do remember that kags and sess we going to have a baby but something happened and the baby died and almost killed her. Kagome wanted to try for another a little bit later but sess was not having it. He didn't want to risk losing her so he kept telling her no when she asked. Eventually she stopped asking and made the potion to destroy her reproductive cycle. Oh they did have a baby before it was a boy. Oh and I remember they were arguing about if sess ancestor was female or male. Turns out it was female and she gave Kagome back her ability to have children again.

I've really been scratching my brain to remember this story. If anyone knows I would appreciate it.

I think it's Mine by Angelic Memories (RATED MA)
dokuga.com/fanfiction/story/743/1

But this won't happen until the last chapters of the story.