Olivia Wilde And Jason Sudeikis Welcome Son
Wilde announced the news on Twitter where she wrote: "Ladies and gentlemen, Otis Alexander Sudeikis has LEFT the building! (I'm the building)."
The House actress also posted a black and white photo of her holding the newborn.
The 30-year-old gave birth two weeks early and had recently spoken about how she considered her bump to be a "badge of pride".
The new parents started dating in late 2011 and became engaged in January 2013.
Sudeikis, 38, recently starred in We're The Millers with Jennifer Aniston and has finished filming a sequel to the comedy Horrible Bosses.