Gaga's initial 2 wins were out of 5 nominations, including for both Record and Song of the Year for "Shallow", which she performed with co-star Bradley Cooper.
Gaga, now an eight-time Grammy victor, won best pop solo performance for "Joanne", while her hit "Shallow" was named best song written for visual media.
Childish Gambino won the coveted prize for best music video for his politically provocative "This Is America". "Thank you for my family", she said.
Keys told CBS news this year´s greater representation from women was "far overdue".
But this year, Gaga, Brandi Carlile and Kacey Musgraves won multiple Grammys.
Gaga, who is to perform later on Sunday, said on Twitter she was "in tears with honour and gratitude". A study released by the University of Southern California's Annenberg Inclusion Initiative days before the ceremony found that of the 899 individuals who had been nominated for the previous six shows, 90.7 percent were men. Emily Lazar, one of the engineers who worked on the album and won alongside Beck, said onstage that she was the first female mastering engineer to win in the latter category.
For the second consecutive year, black hip-hop artists are leading the pack - but observers are still wondering if nominations success can translate into big wins.
Ariana Grande - who had a public falling out with the night's executive producer, Ken Ehrlich, earlier this week over her choice of song, a year after Lorde was denied the opportunity to perform during the telecast - won best pop vocal album for Sweetener.More news: Aston Martin Lagonda All-Terrain Concept teased ahead of Geneva
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"It was when my creativity & self-expression was stifled by you that i decided not to attend".
H.E.R., Chloe x Halle, Margo Price, Dua Lipa, Bebe Rexha and Jorja Smith are also up for best new artist. "I hope the show is exactly what you want it to be and more".
This year's nominees mark a departure from the 2018 Grammys, where Recording Academy CEO Neil Portnow was criticized when he said women need to "step up" when asked about the lack of women in the top categories.
The Staples Center in downtown L.A. played host to some wild fashion moments from the biggest names in music on Sunday, February 10.
Get push notifications with news, features and more. Fifteen-time Grammy victor Alicia Keys will be the first woman to host the ceremony in over a decade.
A performance honoring the legacy of the late "Queen of Soul" Aretha Franklin is also expected.