Around 80 guests gathered for the bash at a private house on Sunday afternoon, including Hudson's stylist Rachel Zoe, and her friends Courteney Cox, Jessica Capshaw and Jennifer Meyer Maguire.
The 32-year-old actress and her fiancé Matt Bellamy have decided against finding out the sex of the baby, which is due in July, so well-wishers were sure to bring only 'gender neutral' gifts, according to People magazine.
'She looked amazing and kept giggling while mingling with friends, nibbling on food and playing games,' said an insider. 'She seemed to have the best time.'
The proud parents to be also appeared at the Chanel hosted benefit in Malibu for the Natural Resources Defense Council's Ocean Initiative, where an onlooker said, 'Kate was just glowing and looked amazing. She and Matt stayed close all night and they seemed very happy together.'