• The American sprinter Allyson Felix beat Usain Bolt’s gold-medal record at the World Athletics Championships on Sunday.
  • Felix won her 12th gold, one more than Bolt’s 11, when she and her team placed first in the mixed-gender 4×400-meter relay.
  • The 33-year-old gave birth to her first daughter prematurely in November and subsequently feuded with her sponsor Nike, which she accused of being unsupportive of pregnant women.
  • Flex wrote an article in The New York Times in which she said the brand asked her to take a 70% pay cut on a new deal postpregnancy and refused to not punish her should her performance decline.
  • Subsequent to her article, Nike changed its policy on pregnant athletes.
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The American sprinter Allyson Felix is now the most successful athlete ever at the World Athletics Championships, having won a record-breaking 12th gold medal.

Felix, 33, secured the gold in the mixed-gender 4×400-meter relay on Sunday, in turn topping Usain Bolt’s record of 11, which had stood since 2013.

The medal performance was also her first since returning to the sport after prematurely giving birth to her first daughter, Camryn, in November.

“So special, to have my daughter here watching means the world to me,” Felix said after the victory, according to AFP. “It’s been a crazy year for me.”

Read more: Decorated Olympian Allyson Felix breaks down the importance of #BlackGirlMagic

Felix gave birth to her daughter via an emergency C-section at 32 weeks late last year after experiencing severe preeclampsia.

Throughout her pregnancy, the American detailed her struggle to maintain her image as a world-class athlete, particularly with her sponsor Nike, which she said was unsupportive of her taking a break from athletics to start a family.

In May, she provided a full account of her feud with Nike in The New York Times, writing an op-ed article in which she said the brand had asked her to take a 70% pay cut on a new contract after becoming a mother and declined to contractually agree not to punish her should her performance decline.

Her deal with Nike, which ended in December 2017, was not extended; however, the brand changed its policy on pregnant athletes after Felix's article was published, preventing female athletes who are pregnant from facing performance-related deductions for 18 months afterward.

Felix posted a statement she received from Nike after the rule change on her Instagram, saying, "Our voices have power."

The 33-year-old signed a new sponsorship deal with Athleta in July, becoming the company's first sponsored athlete.