Polizzi and her fiance, Jionni LaValle, welcomed Lorenzo Dominic LaValle into the world shortly before 3 a.m. at Saint Barnabas Medical Center, MTV reported.
"The world just got another Guido!!!" Polizzi's representative told MTV. "Lorenzo Dominic LaValle has entered the world weighing 6 pounds, 5 ounces. Nicole, Jionni and Enzo are doing great!"
The reality show star disclosed her pregnancy in March, along with the announcement of her engagement to LaValle.
"I mean, I do have a dream wedding," she told MTV News in April. "But I definitely don't even want to talk about it or think about it because I'm not even ready for it yet. I just want my baby first."
The pregnancy was partly documented in "Jersey Shore" and its spinoff, "Snooki & JWoww," MTV reported.