Television has become so raunchy that even Coronation Street is no longer acceptable for children's viewing, says Labour MP Lianne Dalziel.
She said the "Adults Only" television watershed should be moved to 7.30pm as 8.30pm no longer reflected the content of the shows broadcast.
Ms Dalziel put her request to the Broadcasting Standards Authority at the commerce select committee yesterday.
She said she had watched Coronation Street as a child when Ena Sharples ruled supreme, "and I would have to say its content at that stage was unremarkable".
"The most raunchy part of it was Elsie Tanner having a divorce. But there was no question around parents being able to be sure about what their children were watching."
Ms Dalziel said she had seen the British soap opera recently after years of not watching, and "was shocked".
The programme now dealt with "incredibly complex issues, serious issues, that challenge some of the values parents would want to instil in their children".
Adults-only programming starts at 8.30pm and broadcasters have to be careful not to show risque scenes too soon after that.
Ms Dalziel said she was also "shocked" at the number of children who watch Shortland Street. "Anything children are watching from after the news is not safe, necessarily. Nor is the news itself, sometimes."
Although there are no explicit sex scenes on Coronation Street, recent storylines have included a murder, kidnapping, prostitution, transgender issues, an affair and drug addiction.
BSA chief executive Dominic Sheehan said time-slot rules were negotiated between broadcasters and the authority. He would raise Ms Dalziel's point with the broadcasters but he thought they "might have a slight issue with it".
Moving the Adults Only start time to 7.30pm would not necessarily be the end. "What about Shortland Street on at 7pm? Is that okay?" he said.
The authority has recently come under fire for being too prudish in some of its decisions.
Chairman Peter Radich said there was pressure for more liberalisation of what was able to be broadcast. However, the authority could only react to complaints - it could not take proactive action.
He said there was a need for an overhaul of the legislation governing the authority to make the standards more contemporary.
Labour MP David Parker said he was concerned that pressure on broadcasters to be "edgy" to attract viewers meant they were pushing the lines of the standards and the BSA had to push back harder.
Green MP David Clendon said Shortland Street was "quite contemporary in terms of sexuality."
However, soap operas were "caricatures of the real world" and he did not necessarily favour a change in the time slot. National MP Aaron Gilmore said he was more concerned about violence than sexual themes, to which Ms Dalziel quipped, "Wait until your daughter turns 15."