The Brooklyn-based couple's daughter-to-be joins big sister Ramona, 5.
"I'm so pregnant!" the "Hysteria" actress marveled. "This is a great, loose black outfit -- I had to take my shoes off."
Like many expectant stars, the Oscar nominee waited until her second trimester to announce the happy news, and struggled to keep it under wraps while hitting red carpet events and going about her life in Brooklyn with Ramona and Sarsgaard, 41.
"I find it difficult to pretend you're not pregnant, which I had to do," the "Crazy Heart" star admitted. "I didn't let anyone know until three and a half months this time. I went to film festivals. I'm throwing up in the bathroom and having to keep pretzels in my purse, and having to fit into dresses."
After seven years together, the "Lovelace" actor wed Gyllenhaal (older sister to fellow A-lister Jake Gyllenhaal, 31) at a chapel in Brindisi, Italy in May 2009.
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