According to Osho, after attaining the fifth body one no longer takes a gross physical birth. Instead one is reborn in the highest celestial plane with a subtle deva body. Beyond the sixth, even that dissolves into an Ishwar-like form; only after the seventh there is no body at all. Yet nirvana ultimately requires a return to the human condition.
Reach the fifth level and you won’t get a normal body after death—only finer ‘angel’ bodies, then a godlike form, and finally no body; but to be fully free you must come back as a human.