However, while she never officially confirmed it, she showed off her baby bump at an event in New York last month.
"It's all progressing nicely and it's very exciting," she told the new issue of British Vogue.
The 30-year-old, who was snapped by acclaimed photographer Ryan McGinley for the floral photoshoot, continued: "I'm in my second trimester, so I'm I-can-talk-about-it pregnant.
"I'm under strict instructions not to say anything as it would completely defeat the point of everything I've tried to achieve in the last eight years."
The private star added: "It's nice to start a new decade."
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