The 38-year-old actress and her producer husband Scott Stuber - who tied the knot in September - are expecting a baby at the end of June after conceiving while on their honeymoon, and are "thrilled" at the prospect of becoming parents.
Writing on her official website, Molly said: "I am absolutely, positively, downright over the moon to announce that we are pregnant! There are simply no words to describe the feeling . I finally get what they mean when they say pregnant women GLOW.
"Our little bundle of joy is a honeymoon baby, due at the end of June. A first pregnancy is a nerve-wracking experience of course, but mostly we are just thrilled and excited. We can`t wait to meet him or her."
The blonde beauty also admitted she chose an unconventional way of telling her husband he was going to become a father, and opted for delivering the news via a fortune cookie.
Molly added: "I hijacked the fortune cookie and typed a new message so that when he opened his cookie at the end of the meal, he found out he was going to be a daddy.
"You can only imagine how nervous I was during the entire meal (I think I ate a total of two bites.), but the look of surprise and pure joy on his face was priceless."