Nicole "Snooki" Polizzi has DEFINITELY been practicing the "G" portion of the "GTL" lifestyle - everyone's favorite guidette has shed 42 lbs!

The 'Jersey Shore' star, 25, shows off her slim new figure on the cover of the latest issue of Us Weekly magazine.

"I lost it for me," the 4'9" star tells the publication, adding, '"but I also wanted Jionni to know that I can be hot as a mom." Mission accomplished!

Snooki and her fiancé, Jionni LaValle, welcomed their son, Lorenzo, to the world in August, and the new mom confesses that her life is completely different now.

"When you have a baby, everything changes," she tells the magazine.

The new issue of  Us Weekly hits newsstands Friday.