So normal gender is confirmed by the tail base. (link no longer valid)
But if you look at the pics on that link or even go to some of the major breeders and look at pics of their babies. ipardalis, kammerflage, or framschams have lots of baby pics. Theirs all have a confirmed gender. But you will see what I mean about how yours has the really clear circle pattern on the side. But again I am not a pro at this.