The sultry Hollywood star is already mother to baby boy Noah Shannon Green - who she gave birth to last September - and is said to be "very happy" that she and her actor hubby are expanding their family.
A source confirmed the news to the New York Post's Page Six early this morning.
Megan and Brian wed in 2010 in a private ceremony in Hawaii. They met on the set of the film Hope & Faith and first became engaged in 2006, before temporarily calling their engagement off in 2009 and then getting married the next year.
Since having her first child Noah, Megan has admitted to wanting more children.
After Noah was born, the Transformers actress wrote on her Facebook page: "We are humbled to have the opportunity to call ourselves the parents of this beautiful soul and I am forever grateful to God for allowing me to know this kind of boundless, immaculate love."
Megan is currently in the middle of filming the upcoming Teenage Mutant Ninja Turtles film, which is scheduled for release in 2014.
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