Gwyneth Paltrow's 40th birthday: Steven Spielberg, Cameron Diaz and more help her celebrate

Gwyneth Paltrow turned 40 on Sept. 27, but she finally held a birthday bash Friday night (Oct. 5) at Elio's on New York's Upper East Side.

US Weekly reports that among the celebrity guests were Steven Spielberg and his wife Kate Capshaw, Gwyneth's mom Blythe Danner, Chelsea Handler, Kristen Wiig, Ethan Hawke, Beyonce, Jake Gyllenhaal, Cameron Diaz and, of course, Gwyneth's husband Chris Martin.

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Prior to the party, Gwyneth got ready with Diaz -- they had their hair styled by professional stylist Josue Perez.

Earlier this week, Paltrow said of her birthday milestone, "I was really worried about it, leading up to the day, but now I feel really happy and content with my life. I'm excited to move into the next phase. It's much more exciting than I thought it would be."