400 metres hurdles to 400 metres, or one lap of the stadium, and the number of hurdles was reduced to ten. The official height of the hurdles was set to 91.4 cm (3 feet) for men and 76.20 cm (2 ft, 6 inches) for women. The hurdles were now placed on the course with a run-up to the first hurdle of 45 metres, a distance between the hurdles of 35 metres each, and a home stretch from the last hurdle to the finish line of 40 metres. The first documented 400 m hurdles race for women took place in 1971. The International Association
2017 World Championships in Athletics – Women's 100 metres hurdles 2017 World Championships in Athletics – Women's 100 metres hurdles The women's 100 metres hurdles at the 2017 World Championships in Athletics was held at the London Olympic Stadium on . World record holder Kendra Harrison (USA) was the slowest time qualifier to the final, while 2011 champion Sally Pearson (AUS), Dawn Harper-Nelson (USA) and Pamela Dutkiewicz (GER) were the top three fastest. It was Harper-Nelson's fifth straight championship and fourth final. In the final, Harrison was out slightly faster than Pearson, Christina Manning (USA) and heptathlete Nadine Visser over the first hurdle. Harrison held the lead until she rattled