Perhaps one of the most memorable moments of the night was tennis star Serena Williams and model Karlie Kloss publicly announcing their pregnancies as they walked the cream, red and blue carpet.

Met Gala: The biggest night in fashion as it happened

Williams, 41, is expecting her second child with husband Alexis Ohanian, and Kloss, 30, her second child with husband Joshua Kushner.

The dress code of the evening, hosted at New York's Metropolitan Museum of Art, was "In honour of Karl", meaning celebrities were inspired by late Chanel designer Karl Lagerfeld.

The retired tennis player wore a black mermaid gown, with silver edging designed by Gucci, and multiple strings of pearls around her neck and a layered pearl headband.

Her husband proudly placed his hand on her stomach as the couple posed together. Speaking to reporters, Williams said there were "three of us" on the carpet.

Meanwhile, Kloss wore an outfit designed by Northern Irish fashion designer Jonathan Anderson. Her black gown featured Lagerfeld's signature strings of pearls.

Speaking to Vogue, she said: "I'm so happy, this is the first time I'm sharing my news, so it's very special.

"This is the first time I'm on a red carpet pregnant and it's a super special moment, also kind of vulnerable - so I don't know how to style a belly. I can't imagine a more special moment."

Rounding off the expectant mothers was singer Rihanna, who, despite keeping everyone waiting for more than an hour, graced the carpet in an extravagant bridal-inspired look, featuring Lagerfeld's favourite flower - camellias.

The 35-year-old singer is expecting her second child with partner ASAP Rocky, who walked the carpet alongside her.

"[This pregnancy] is so different from the first one," the singer told Entertainment Tonight while on the carpet. "No cravings, tonnes of nausea, everything's different, but I am enjoying it," she said.

Other standout moments from the evening included singer Doja Cat channelling Lagerfeld's beloved pet cat Choupette as she transformed into the feline with the use of prosthetics on her face and cat ears.

Actress Florence Pugh also debuted her freshly shaved head, which was crowned with a towering black feathered headpiece. She said she had undergone the transformation for her upcoming film, We Live In Time, and had kept the look secret for three weeks ahead of the dramatic reveal.

Vogue editor-in-chief and Met Gala co-chair, Dame Anna Wintour described the event as an "emotional night" as she paid tribute to her friend. She described Lagerfeld as "the chicest designer that you can ever imagine".