The reality couple celebrated the happy news at the home of LaValle's parents in East Hanover, NJ on Saturday, reports Radar Online.
Snooki's Jersey Shore co-star Jenni 'JWoww' Farley was in attendance for the party, as were the star's parents Andy and Helen Polizzi.
Helen was photographed bringing a large bouquet of flowers and balloons for her daughter.
Snooki confirmed her pregnancy and engagement to LaValle last Wednesday (March 7), following weeks of speculation that she was expecting a baby.
LaValle later joked on Twitter that he and Snooki have already nicknamed their unborn child 'ShortnTan'.
Snooki will apparently give birth this summer.
> Jersey Shore Deena Cortese: 'Snooki will be a great mum'
> Jersey Shore's Vinny Guadagnino: 'Snooki pregnancy was a shock'