The novel Fire by Kristen Cashore (of Graceling fame) actually does have a case where a lack of a child is a problem for a female protagonist on a purely emotional level. You find out over the course of the story that she had deliberately sterilized herself out of the fears that her extraordinary beauty and mind control powers would be passed on to another generation though her, the last possessor of them (the novel is in part a deconstruction of some of the more visible traits of Mary Sues). Meanwhile, she loves children and desperately wishes she could have one.
Re: creeping?
Go for it!