No specific due date was announced, but O'Dell and her husband, Keith Zubchevich -- who married last year -- are expecting the new arrival next summer.
"My husband Keith and I are over the moon!" O'Dell said in a story Wednesday on the entertainment show's Web site.
The couple met in a security line at Burbank's Bob Hope Airport, "Access Hollywood" said. Zubchevich has two sons -- Tyler, 11, and Carson, 7 -- from a previous marriage.
O'Dell, 40, is a six-time Emmy Award nominee. She was once named as one of "Television Week's" 10 Most Bankable Stars in Syndication, and made Shape magazine's list of 20 Hottest Stars Right Now.
O'Dell and her "Access Hollywood" co-host Billy Bush, will serve as co-hosts of the 118th Tournament of Roses Parade Jan. 1 on NBC.