Vivienne Pattison from the campaign group Mediawatch UK has made the call following similar comments by the Daily Mail's film critic.
Speaking on Premier's News Hour, about another 12A film, she said: "I find it incredibly difficult to justify the fact that [with] Spectre - which is an excellent film but is a 12A - you can take a six year old to see it and they can see someone getting their eyes gauged out and I don't think any of us think that is appropriate."
Talking about the hypocrisy of films at the cinema and on DVD, she said: "There is no such thing as a 12A rated DVD. If you buy a DVD and it's a 12 you can't sell it to someone under the age of 12 but if you go to the cinema and there is a 12A rating you can take a five year old to see it."
Brian Viner from the Daily Mail said it was watching a preview of the latest instalment of the Hunger Games that caused him to want to take action.
Writing in the newspaper today, he said: "As the Mail's film critic, I see about 250 features a year, so am practically programmed never to jump out of my seat.
"But with this mutant attack, even I achieved a small vertical lift-off. And if it alarmed me, what will it do to the children watching?"
The 12A rating was introduced 13 years ago to give parents the power to choose whether a film was suitable for their child.
David Cooke from the British Board of Film Classification said as children develop at different speeds, parents are better placed to judge whether a particular film would give their child too intense an experience or not.'
But Mr Viner rejects that. He said: "Plainly, it is time to reconsider the 12A classification. The notion that the disturbing content of a film might somehow be diminished just because a child is sitting next to a mum or dad, an aunt or uncle, is obviously ridiculous.
"Something has to change, before one or more of these 12A films wreak irreversible emotional damage. If, that is, it hasn't happened already."
Listen to Vivienne Pattison speaking to Premier's Antony Bushfield on the News Hour.