King shared the happy news in an Instagram post featuring her and Newman's 16-month-old son James Knight.
The actress has been open about her struggle to conceive, which included five miscarriages. She and Newman have been married since 2007.
King can currently be seen on Hart of Dixie, which wrapped filming on Season 4 in October. Newman most recently directed the music video for Taylor Swift's new single "Style."
Tour the Hart of Dixie set with star Scott Porter