The 35-year-old actress, who married Pratt in 2009, will welcome their first baby in fall this year, her representative confirmed, reported People magazine.
Last year, Faris said that she and her husband would love to have a big family.
"I would love to have eight kids. We want to populate. I hope I wouldn't get lazy, but I love being around kids. Sometimes I relate to them in an adult manner, which is a little annoying, but I would love to be a mom at some point," she had said.