| Women's 400 metres at the Pan American Games |
|---|
| Athletics at the 2003 Pan American Games | ||
|---|---|---|
| | ||
| Track events | ||
| 100 m | men | women |
| 200 m | men | women |
| 400 m | men | women |
| 800 m | men | women |
| 1500 m | men | women |
| 5000 m | men | women |
| 10,000 m | men | women |
| 100 m hurdles | women | |
| 110 m hurdles | men | |
| 400 m hurdles | men | women |
| 3000 m steeplechase | men | |
| 4 × 100 m relay | men | women |
| 4 × 400 m relay | men | women |
| Road events | ||
| Marathon | men | women |
| 20 km walk | men | women |
| 50 km walk | men | |
| Field events | ||
| High jump | men | women |
| Pole vault | men | women |
| Long jump | men | women |
| Triple jump | men | women |
| Shot put | men | women |
| Discus throw | men | women |
| Hammer throw | men | women |
| Javelin throw | men | women |
| Combined events | ||
| Heptathlon | women | |
| Decathlon | men | |
The final of the Women's 400 metres event at the 2003 Pan American Games took place on Friday August 8, 2003, with the heats staged a day earlier. Hazel-Ann Regis won the only silver medal for Grenada at the 2003 Pan American Games.
| Gold | Ana Guevara |
| Silver | Hazel-Ann Regis |
| Bronze | Aliann Pompey |
| World Record | 47.60 | October 6, 1985 | | |
| Pan Am Record | 49.61 | August 5, 1991 | |
| Rank | Athlete | Heats | Final | |
|---|---|---|---|---|
| Time | Rank | Time | ||
| 1 | 52.22 | 2 | 50.36 | |
| 2 | 52.21 | 1 | 51.56 | |
| 3 | 52.23 | 3 | 52.06 | |
| 4 | 52.37 | 4 | 52.23 | |
| 5 | 52.62 | 5 | 52.53 | |
| 6 | 52.76 | 7 | 52.83 | |
| 7 | 52.23 | 6 | 52.96 | |
| 8 | 53.13 | 8 | 53.26 | |
| 9 | 53.18 | 9 | ||
| 10 | 53.23 | 10 | ||
| 11 | 53.41 | 11 | ||
| 12 | 53.53 | 12 | ||
| 13 | 54.24 | 13 | ||
| 14 | 55.22 | 14 | ||
| 15 | 56.30 | 15 | ||
| 16 | 1:01.79 | 16 | ||
| — | DNF | — | ||
| — | DNS | — | ||