Sienna Miller and fiance Tom Sturridge, star of The Boat That Rocked, have reportedly welcomed their first child into the world this weekend in London, according to a report in Us Weekly.

The English actress, famous for her roles in Alfie, Layer Cake, G.I Joe and Factory Girl, is notoriously private, so it’s no surprise that at the moment the sex or name of the baby are unknown.

Ms Miller’s previous engagement, to Alfie co-star Jude Law, ended in 2005.

sienna miller

Sienna Miller has given birth, according to a US entertainment mag

Her relationship with 26-year-old Sturridge began just over a year ago.

Ms Miller hasn’t spoken very much publicly about her pregnancy, but did touch on the subject briefly in an interview with Vogue UK in April.

She told the fashion magazine: “I'm feeling fine. It's all progressing nicely and it's very exciting."

The fiercely private star has also given her baby bump a few public outings this year, including to Restaurant Gordon Ramsay in London with Sturridge, for his pal Robert Pattinson’s birthday slap-up, according to Us Weekly.

Besides acting and preparing for motherhood, Miller, recently, has also been taking a stand against the press. She was one of the celebrities who appeared at the Leveson inquiry and described her horror at being chased by paparazzi.

It’s thought she will receive a large payment from News International after The News Of The World admitted hacking into her phone.

More stars who are expecting babies in 2012:

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  • Lake Bell

    Actress <a href="" target="_blank">Lake Bell is pregnant</a> with her first child with husband Scott Campbell.

  • Gabby Hoffman

    "Girls" actress <a href="" target="_blank">Gaby Hoffmann is expecting</a> her first child with cinematographer boyfriend Chris Dapkins.

  • Kourtney Kardashian

    Kourtney Kardashian is <a href="" target="_blank">pregnant with her third child</a> with partner Scott Disick.

  • Jenni "JWoww" Farley

    JWoww, who's expecting her first child with fiance Roger Mathews in July, is set to welcome a little baby girl.

  • Christina Aguilera

    Aguilera is reportedly expecting her second child, her first with fiance Matthew Rutler.

  • Scarlett Johansson

    The actress is reportedly expecting her first baby with fiance, Romain Dauriac.

  • Mila Kunis

    Kunis is reportedly expecting her first child with fiance Ashton Kutcher.

  • Stacy Keibler

    Keibler is expecting her first child with new husband Jared Pobre.

  • Siri Pinter

    Carson Daly and longtime love Siri Pinter are expecting their third child.

  • Snooki

    Snooki is expecting her second baby with fiance Jionni LaValle.

  • Alyssa Milano

    Milano is expecting her second child, a baby girl, with husband David Bulgari.

  • Christina Ricci

    The actress is expecting her first child with husband James Heerdegen.

  • Rachel Bilson

    Bilson is reportedly expecting her first child with longtime boyfriend Hayden Christensen.

  • Kristen Bell

    Bell is expecting her second child with Dax Shepard.