Vieira was born in Manaus, Amazonas, Brazil. She started training Brazilian Jiu-Jitsu and when she was twelve she started training in Judo. She holds black belts in both disciplines.[5][9] She is also a decorated wrestler with multiple prestigious titles, including Brazilian national wrestling championship.[10] She studied law at University Nilton Lins, but dropped out in order to pursuit a career in mixed martial arts.[11] She eventually transitioned to MMA and trained under Marcinho Pontes, who was José Aldo's early coach at Nova Uniao Manaus gym.
Mixed martial arts career
Early career
Vieira fought all of her fights in Brazil where she made her professional debut on 2 October 2014, at Circuito de Lutas: Fight Night 4 in São Paulo. She faced Juliana Leite and knocked out Leite in round two.[12] She continued to win the next 5 fights under Mr. Cage and Big Way Fight Night banners where she won the Mr. Cage bantamweight title.[3] Vieira amassed a record of 6–0 in 17 months prior to being signed by the UFC.[4][9][13]
Ultimate Fighting Championship
Vieira made her promotional debut on 1 October 2016, at UFC Fight Night: Lineker vs. Dodson in Portland, Oregon, United States. She faced Kelly Faszholz[14] and ultimately edged out her opponent to win by split decision.[15] In the post fight interview, Vieira explained her difficulty with weight cutting for this fight. Two days prior to the scheduled fight, she needed to drink one liter of water to provide a urine sample to USADA, which interfered with the process of her weight cut prior to the USADA visit.[16]
Vieira was originally expected to face Sara McMann at UFC 214 on 29 July 2017.[21] However, the fight was moved to UFC 215 on 9 September 2017.[22] Vieira won the bout via arm-triangle choke submission in the second round.[23]
Vieira fought Irene Aldana on 14 December 2019, at UFC 245.[29] She lost the fight by knockout in the first round.[30]
Vieira was scheduled to face Marion Reneau on 9 May 2020, at UFC 250.[31] Due to the event being relocated to the United States, Vieira being unable to compete due to visa issues:[32] However, on 9 April, Dana White, the president of UFC announced that this event was postponed to a future date[33] Instead, Vieira was scheduled to face Yana Kunitskaya on 1 August 2020, at UFC Fight Night: Holm vs. Aldana,[34] and on 15 July 2020, it was announced that the bout was moved to UFC Fight Night 174 on 8 August 2020.[35] Subsequently, Vieira was removed from the card on 30 July for undisclosed reasons and replaced by Julija Stoliarenko.[36]
The bout with Reneau was rescheduled and was expected to take place on 27 September 2020, at UFC 253.[37] However, Reneau withdrew from the bout citing an undisclosed injury and she was replaced by Sijara Eubanks.[38] Vieira won the fight via unanimous decision.[39]
The bout with Yana Kunitskaya was rescheduled and eventually took place on 20 February 2021, at UFC Fight Night 185.[40] At the weigh-ins, Vieira weighed in at 138 pounds, two pounds over the women's bantamweight non-title fight limit. She was fined 20% of her purse which went to her opponent, Kunitskaya, and the bout proceeded at a catchweight.[41][42] Vieira lost the fight via unanimous decision.[43]
Vieira was scheduled for a rematch against Sara McMann on 28 August 2021, at UFC on ESPN 30.[44] However, McMann announced in mid August that a "reinjury" forced her out of the bout.[45] Instead, Vieira was scheduled to face Miesha Tate on 16 October 2021, at UFC Fight Night 195.[46] However, on 22 September, the bout was pulled from the card when Tate tested positive for COVID-19.[47] The bout was rebooked to 20 November 2021, as the main event of UFC Fight Night 198.[48] Vieira won the bout via unanimous decision.[49]
Vieira faced Holly Holm on 21 May 2022, at UFC Fight Night 206.[50] She won the fight via controversial split decision.[51] 18 out of 20 media outlets scored the bout as a win for Holm.[52]
Viera was scheduled to face Macy Chiasson on 13 January 2024, at UFC Fight Night 234.[57] However, Vieira was pulled as a result of an injury and the bout was scrapped.[58]