Margaret Nyairera Wambui

Margaret Nyairera Wambui is a Kenyan middle-distance runner born on September 15, 1995, in Nyeri. She specialized in the 800 metres and achieved significant international success before rule changes affected her eligibility.

Wambui won gold at the 2014 World Junior Championships in her first international competition. She won bronze at both the 2016 World Indoor Championships and the 2016 Summer Olympics, where she set a personal best of 1:56.89 in the final. In 2019, she was disqualified from IAAF women's competition due to new regulations for athletes with certain biological characteristics, including testosterone levels above 5 nmol/L.

Wambui declined to take medication to suppress her testosterone levels and has not competed internationally since the rule changes. Her case was featured in the 2022 documentary film Category: Woman, which examined the experiences of athletes affected by these regulations.