SPOILERS (Don't read if you haven't seen the movie)
>IMO, Palpatine had no intention of saving Padme. He offered an explanation, so he wouldn't turn on his new master. Full of deception, he is. At least indirectly, of course, Vader is responsible.
That makes sense.
>IIRC, the Emperor informs Vader about Luke in Episode V. Vader learns about Leia from Luke in Episode VI.
Is it safe to assume that the Emperor knows that Padame gave birth before she died in the end of episode III?
Semper ubi sub ubi.