If Rand learns that Elayne is pregnant and that Aviendha will have children of him, he might likely be convinced that it's even more urgent to fake his death to protect his family and basically live on in his children, especially if there will be another attempt of the Shadow to kill one of Rand's women.

Besides that, as the Rand knows know, the Forsaken gave an example of dying and coming back in a "disguise" to trick the Light, so to speak.