Image copyright Gary Moyes/ITV Image caption Marek Larwood, Iain Stirling and Scarlett Moffatt star on ITV2's Celebability

ITV will no longer commission comedy shows with all-male writers' rooms, the broadcaster's head of comedy has said.

Saskia Schuster said she realised last year that "an awful lot of my comedy entertainment shows are made up of all-male writing teams".

She said: "Too often the writing room is not sensitively run. It can be aggressive and slightly bullying."

She has now changed ITV's contracts, and female writers have been hired to join shows like ITV2's Celebability.

There has been "a significant lack of shows written by women or with women on the writing teams", she said.

Last year, when reviewing the gender balance of sitcom scripts she was sent, she realised that for every script she received from a female writer, she got five from men.

After consulting writers, producers, agents and performers, "the first thing I did was I changed my terms of commissioning," she told Channel 4's Diverse Festival in Bradford on Monday. "I won't commission anything with an all-male writing team."

Ms Schuster has launched a scheme called Comedy 50:50 to encourage more female comedy writers. She said female writers struggle because:

It is difficult to compete for jobs with men who have more writing credits

They can't find producers who "get" their voice and can develop their script to its full potential

They don't thrive as the lone female voice in a writers' room

"There can all too often be a sense of tokenism towards the lone female," she wrote on the Comedy 50:50 website. "Or the dominant perception is that the female is there purely so the production can hit quotas."

She has now changed ITV's contracts so any shows that are commissioned or recommissioned "must aim towards 50:50 gender representation".

Image copyright Getty Images Image caption Brona C Titley has been hired to join the Celebability writers' room

Comedy 50:50 has set up a database which currently has details of 460 female writers. Many producers had complained that "there aren't any female writers [or] we don't know where to find them", she said.

Ms Schuster also runs events where she says she "forces" her producers to have 10-minute conversations with three female writers. She has set up confidence workshops and is launching a mentoring network next month.

She has assigned young female writers to shadow shows like Roman sitcom Plebs, which is written by two men, and also hopes to extend the equality target to cover directors and crew members.

Writer Brona C Titley has been brought onto the team for ITV's panel show Celebability, which didn't have any female writers for its first two series. She told the Diverse Festival that she had been in 15 writers' rooms in recent years, and had been the only woman in eight of them.

"If you have the same type of writers in terms of race or sexual orientation or gender, then you're only getting one kind of joke, and if you've got different voices in the room, you're getting different kinds of jokes," she said.

"You want to represent the wide audience that's watching. You want diversity in voice, or else it won't be as funny because it won't be appealing to as many people."

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