The Film and Video Labelling Body is pushing for law changes to make cinemas screen warnings before films start.
This follows the release last month of A Star Is Born - a remake of a Hollywood classic - starring Lady Gaga and Bradley Cooper.
Within days of its first screenings, police and the Mental Health Foundation had been contacted by people distressed by the film's content.
An Auckland woman, who asked not to be named, said the film's final scene left her traumatised.
"You come home everyday wondering if it's gonna have been today because someone you love has been on the brink for months or years and yeah, it was just horrific to watch it play out in a movie. You know, you go to the movies, I go for entertainment, but not for something that traumatic," she said.
She said she received no warning of the scene.
"Given how terrible our rates of suicide are, I almost wonder - and I'm not really pro-censorship in many things - but I almost wonder if it needed to be edited or at the beginning of the film even a warning," she said.
A warning was added to the movie's posters by the censor's office shortly after the film started screening in New Zealand. However, this movie-goer said she didn't see it on the poster, and it was not sufficient considering the movie's content.
The warning followed dozens of calls to the Mental Health Foundation from viewers who found a suicide scene "severely distressing".
Police also told the Chief Censor two vulnerable young people were "severely triggered" by it.
Sharon Walling is the general manager of The Film and Video Labelling Body, which rates unrestricted films and issues classification labels. The reaction to A Star is Born has led to a discussion with Reading Cinemas, she said.
"We're going to look at whether we can actually display the certificate on the screen prior to the film commencing, so that if they're not previously aware of what the rating or the consumer advice notes are then they can become aware before the film starts," Ms Walling said.
Between 1968 and 1994, cinemas were required to show a film's classification and warnings on screen for eight seconds.
But when the law changed in 1993 - this was no longer the case.
By the end of next week, cinemas would be supplied with the resources needed to show a film's classification on the big screen, Ms Walling said.
"I'm confident that they exhibitors will consider taking this on board, because they obviously want to ensure that their customers are not traumatised by anything they see either. So, I feel confident that we can work with the industry to get this through quickly," Ms Walling said.
While cinemas won't be required to display the classification, Ms Walling said the law needed to change to force them to do it.
Under the current legislation, cinemas are only required to display a film's classification and warnings on a poster.
Chief Censor David Shanks said that was not good enough.
"Often that can be in the form of a wall chart or a set of classifications put together in the foyer that may be missed by cinema-goers," Mr Shanks said.
Mr Shanks said he was working with the The Film and Video Labelling Body to display a film's classification on a theatre screen.
In a statement, Internal Affairs Minister Tracey Martin said she agreed the Classification Act needed an upgrade.
"I'm talking to David Shanks and officials regularly and agree that we need changes to the Classification Act to bring it up to date and deal with this sort of issue."
RNZ has contacted Event Cinemas, Hoyts and Reading Cinemas for comment.