WOMEN who watch porn feel short-changed by their fellas failing to match up to the studs, researchers say.

They have “unrealistic expectations” in the trouser department — and about their partners’ stamina.

3 As more women watch porn - real life expectations change Credit: Photographers Choice - Getty

It means unsuspecting chaps risk being rated flops in bed, a study by psychologists found.

The revelation — amid a boom in women viewing internet porn — led to scientists behind the research warning yesterday: “Genitalia can be digitally or cosmetically altered, depicting larger than average penis size.”

Sex expert Kaitlyn Goldsmith, who led the study in Canada, said of romps in X-rated films: “Intercourse is shown to last longer than average, men sustain erections longer and women experience orgasms more easily than in real-world encounters.”

The research at the University of New Brunswick involved 1,000 adults, two thirds of them young women.

3 It is getting tougher for men to please women in bed because of porn Credit: Getty

It found porn viewed by females was “linked to consumers’ dissatisfaction with their partners’ appearance”.

Women ran the risk of “unrealistic expectations for sexual performance”.

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The shock for fellas comes after Pornhub, the world’s largest adult site, revealed more than a quarter of online visitors are now women.

The top search terms they enter include the words “big d***”.

Relationship charity Relate has warned online porn is fuelling a crisis in bedrooms, with two in three people saying their sex life is disappointing.