The Mean Girls star, who is expecting her first child with fiancé Thomas Sadoski, first revealed that she was pregnant in late November, showing up to a Givenchy press launch in a chic black mini dress that hugged every curve -- including her baby bump.
ET confirmed that Seyfried was engaged to Sadoski in September. The two first met in 2015 while starring together in the play, The Way We Get By, before working together again on a film, The Last Word, earlier this year. The two then started dating in March.
See more on Seyfried's big baby news in the video below.