Though Kate Winslet is no stranger to donning vintage clothes for the many historical films she's starred in throughout her career, the actress' latest project, A Little Chaos, posed an interesting new challenge — wearing a corset while pregnant!

"It was like, back to basics, here we go. [But] the corset from that time period actually stops right at your navel, so that was not an issue. It was really just what to do with the boobs!" the 39-year-old said of filming while expecting her and hubby Ned Rocknroll's son Bear Blaze, now 18-months, in a new interview with Us Weekly.

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Kate as Sabine De Barra in A Little Chaos.

In A Little Chaos, Kate — who also has kids Mia, 14, and Joe, 11, from previous marriages — plays Sabine De Barra, a landscape artist hired to design the lavish Palace of Versailles gardens during the 17th century.

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Though she kept her pregnancy a secret from the cast and crew at the start of the flick's filming, she confessed she did tell one person she was expecting — actor and director Alan Rickman, 69.

kate winslet pregnant

Kate while pregnant with her son, Bear Blaze, in October 2013.

"[I said], 'You just might have to accept that my boobs are going to get massive,'" Kate said with a laugh during her sit-down with the mag. "And he was like, 'I think I can cope with that.'"

A Little Chaos hits theaters this Friday, June 26.