The 32-year-old Shevoke founder revealed the exciting news on Saturday, sharing clips from her gender reveal party alongside partner Damon Collina.
"A beautiful miracle chose us to be her parents, we can’t wait to meet you little bubba," she wrote.
Lisa and Damon have been dating since last year, following her appearance on Bachelor In Paradise.
The couple also took to Instagram over the weekend to share their gender reveal, popping a balloon at a party attended by close friends and family.
"It’s a girl 💕🦄🌸🎀 Thank you to all our amazing family and friends who witnessed this special moment with us! We had no idea of the gender until this moment," she wrote to her followers.
Samuel Cochrane, Davey Lloyd and Megan Marx and Keira Maguire were among the fellow Bachelor stars to congratulate Lisa and Damon on their announcement.
Lisa first shot to fame as a contestant on the 2014 season of The Bachelor, competing for the heart of real estate agent Blake Garvey. She returned to reality TV early last year, with a stint on spin-off Bachelor In Paradise where she met and Luke McLeod. The couple decided to leave the show to focus on their relationship, only to break up several weeks later.
Congratulations to the couple!