The actress, 31, who's expecting her second child with rocker boyfriend Matthew Bellamy, says she's settling into her role as a mom-to-be – and that means enduring morning sickness.
"I'm pregnant, and I'm really sick," she tells The Times, with a laugh. "But I couldn't say that because you really want to keep it as quiet as you can for the first trimester."
Hudson, who has a son, Ryder, 7, with ex-husband Chris Robinson, says she originally tried to keep her baby bump a secret – even from her closest pals.
"My friends all thought I was depressed because I wouldn't leave the house," she says. "But I didn't want anyone to know for a long time. I was just hoping that all of a sudden, I could show up somewhere with a big belly."
She adds: "But, of course, you're somewhere in L.A., and somebody says something, and it ends up somewhere."
And as she awaits the due date of her baby, which she says is in the summer, there's only one problem.
"I babble a lot," she says, citing "pregnancy brain." "I forget words, and how to put sentences together. I just give up."
As for life post-pregnancy, Hudson says she's teaming up with her mother, Academy Award-winning actress Goldie Hawn, for a new project: "We're developing something that will happen in the next 18 months, but I can't give you plot outlines yet."