Farley, who also co-starred on "Snooki & JWoww" with Nicole "Snooki" Polizzi, is engaged to Roger Matthews.
"Merry Christmas from within!" Farley wrote in a message Wednesday.
"Roger and I couldn't have asked for a better Christmas gift this year! We wanted to share this exciting news with you all first because you have been a part of our lives these past few years and seen the love between Roger and me develop and blossom," she said. "We are so excited to share this new chapter of our lives with you as we become parents and create more memories with a new addition to our family! Thank you for all your love and support and for being there for us throughout the years! We are extremely happy and cannot wait for our bundle of joy to arrive!"
Farley did not disclose her baby's gender or anticipated due date.
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