The No Doubt star is expecting her third child with her rocker husband Gavin Rossdale, another boy, and her famous friends turned out to help her mark the baby's impending arrival at a bash in Los Angeles.
Paltrow, Richie and Alba all attended the party at the Hotel Bel Air, along with British actress Kate Beckinsale and talk show host Chelsea Handler, according to E! News.
Stefani documented the day in a series of posts on her Instagram.com page, sharing a picture of blue-themed doughnuts and candy in honour of her baby boy, and thanking her manager's wife Shelli Azoff for organising the day.
The singer wrote, "Baby shower!!! Can't believe I'm pregs (pregnant) thanku (sic) Shelli Azoff for a beautiful girly day = blessed... lucky girl I am."
Stefani and Rossdale are already parents to sons Kingston, seven, and Zuma, five.