Is Carrie On The Nest?
When Carrie came back, she was bundled up and you couldn't see her body. I know that Clair Danes is pregnant and if Carrie was off her medication, it's not out of the question that she was either sexually assaulted or promiscuous while she was in prison.
That would be a hell of twist. Next season would be all able Carrie getting her sanity back while dealing with a pregnancy she might not even remember conceiving. And of course there is the obligatory Saul and Carrie save the world story arc.