Cavallari, 26, is married to NFL star Jay Cutler. The two are already parents to 14-month-old boy Camden.
"We want to have a second sooner rather than later," the Laguna Beachalum told E! News in September. "We're working on it! Before Camden was born, I thought I'd be pregnant again by the time he was six months, but I definitely wasn't ready. Now, I'm finally ready."
Cavallari and Cutler started dating in the fall of 2010. They got engaged in April 2011, but split three months later. They reunited shortly thereafter.