Ronda Rousey Reveals That Years of Concerning Concussions Led to Her Abrupt Retirement from Fighting 

Ronda Rousey is finally telling the world why she retired from MMA.

While promoting her upcoming memoir Our Fight in an Instagram Live interview on Thursday, the former UFC women’s bantamweight champion, 37, directly addressed the reason why she suddenly left the sport in December 2016 after a TKO loss to Amanda Nunes.

"My concussion history that I had to keep secret for years so I would be able to continue to compete and perform, that’s basically why I had to retire," she said on Instagram Live when her interviewer and sister, Maria Burns-Ortiz, (who is the book's co-author) asked her to list facts that her fans don't know about her.

Before 2015, Rousey was an Olympic judo bronze medalist who had never lost a fight in MMA and had defended her UFC title six consecutive times. The first loss of her career came at the hands of Holly Holm at UFC 193 in December 2015.

Holm, 42, kicked Rousey in the head and knocked her out to win the fight.

On Instagram Live, the former WWE performer, also finally spoke publicly about that loss for the first time.

"I think that there was just so much to [my feelings about that loss], that I couldn’t talk about it in the form of like an interview or an article or anything like that, or there would be several filters between my words and people reading it,” she said, adding that the reason she took the loss so poorly also had to do with her medical history.

“So much had to do with having so many concussions when I was in judo before I even got into MMA, I couldn’t talk about it at all when I was doing MMA because it would literally put a target on my head, and I might not have been allowed to compete any further."

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Rousey, who was a WWE entertainer from 2018-2023 after she retired from the UFC, said that even after she retired, publicly discussing her history of concussions would have jeopardized her spot in the wrestling entertainment organization.

"Same thing with WWE. They have a complicated history with their performers getting concussions, and it would be a bad look on them. So I felt like I really couldn’t talk about it at all," Rousey admitted, adding that she felt like a memoir was the only way she could talk about the end of her career.

At the end of the conversation, Rousey said that her "body" made the decision that it was time for her to retire after two consecutive losses, though she appeared to be at the height of her career.

Our Fight will be available on April 2.