Sorry, I have no personal experience, but when I was working in the pharmacy one of my customers DD's had the same thing, I've never heard of the vaseline thing though?

anyway, She was prescibed a hormone cream, Ovestin? I think? to apply.
From what I understand its fairly common and I think it depends on the (not severity, but can't think of the word!) condition of it as to wether its left to separate itself or if medication is needed.
HTH a little