Runners take part in the 2019  London Marathon, over Tower Bridge in London, Sunday April 28, 2019. (Aaron Chown/PA via AP)

LONDON (AP) — A British nurse who ran the London Marathon in her uniform says she has been denied a Guinness World Records listing because she wasn't wearing a skirt.

Jessica Anderson ran last week's marathon in a time of 3.08:22, half a minute faster than the existing marathon record for a woman in a nurse's uniform.

Anderson says she was informed that her uniform of medical scrubs with trousers didn't meet Guinness's rules for a nurse's uniform: a blue or white dress, apron and a traditional cap.

Anderson told Runner's World magazine the rules were outdated and reinforced "old gender stereotypes."

Guinness World Records said Saturday "it is quite clear that this record title is long overdue a review, which we will conduct as a priority in the coming days."

Lukas Bates wearing a costume of the Queen Elizabeth Tower (known as Big Ben) is helped by an official as he attempts to get past the finishing line, during the 39th London Marathon in London, Sunday, April 28, 2019. (AP Photo/Alastair Grant)
Security and police walk down the Mall as preparations are made for the finish line area of the 39th London Marathon in London, Sunday, April 28, 2019. (AP Photo/Alastair Grant)
A competitor in the 39th London Marathon, centre, turns round and raises his arms in triumph after he competed the marathon and shares an moment with his friends as they look back down the course in London, Sunday, April 28, 2019. (AP Photo/Alastair Grant)