She also picked up three other awards, for best female pop artist, best tour, and best pop album for Reputation, the biggest seller of 2017.
"When I was pregnant, I was so influenced to be like, "Yo, I gotta do this".
Swift owned the night from the moment the 2018 AMAs ceremony kicked off, opening the show in spectacular fashion with a fiery, witchy performance of the Reputation track "I Did Something Bad" alongside her famous mechanical snake, Karyn. The night opens with Taylor Swift making her first awards-show performance in almost three years, and tributes promise to provide memorable moments.More news: Google drops out of Pentagon's $10 billion cloud competition
"I really want to thank my daughter", said Cardi B, who gave birth to Kulture Kiari Cephus in July. Khalid, Quavo and Offset were some of the audience members dancing along, while others sang and some even filmed her with their phones. J Balvin emerged as Cardi busted out some salsa moves with her dance partner.
The 28-year-old just wrapped up the USA leg of her Reputation tour.
Among the performances, a tribute to the late Aretha Franklin is planned.
Camila Cabello was also a big victor on Tuesday night.More news: U.S. military moves command center as Hurricane Michael bears down
XXXTentacion's mother, Cleopatra, accepted the prize on stage. It was days after he was named best new artist at the BET Hip-Hop Awards.
The politically charged 2018 American Music Awards produced dismal viewership, setting an all-time low rating for the annual special.
Elsewhere, Swift was not the only major celebrity to perform, with both Mariah Carey and Jennifer Lopez taking to the stage.More news: Soyuz rocket carrying crew to ISS malfunctions during launch
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