Amanda Seyfried reveals she's expecting her first child with fiance Thomas Sadoski

Amanda Seyfried is going to be joining the mommy club.

The 30-year-old actress announced her pregnancy at a Givenchy event in New York City on Tuesday, just two months after confirming her engagement to Thomas Sadoski. At the event, Seyfried was clad in a sweet black mini dress that showed off her tiny baby belly.

This will be the first baby for Seyfried and Sadoski and the two haven't revealed whether they're planning to marry before or after baby.

Seyfried and her fiance, 40, met while working together on the off-Broadway show The Way We Get By last year, and started dating after reuniting on the set of their film "The Last Word."

Congrats to the soon-to-be parents.

PHOTOS: A look at the happy couple