Last year's X Factor final featuring Christina Aguilera and her backing dancers in a racy routine was "at the very margin of acceptability", broadcasting watchdog Ofcom has ruled.
The "sexualised" pre-watershed scenes, aired in December on ITV1 at the end of the seventh series, sparked 2,868 complaints to the media regulator.
US singer Christina donned a short black dress while her female dancers, who were bent over chairs, wore suspenders, bra tops, fishnet stockings and basques in the raunchy routine.
Ofcom said that over one million young children were watching the live final, and 50,000 saw the repeat the following morning.
It stated that Rihanna's performance on the same night, where she removed a wraparound dress to parade on stage in a bikini, was not inappropriate for the time when it was broadcast.
But it said that Christina's burlesque-style routine "was at the very margin of acceptability for broadcast before the 9pm watershed and especially" when it was repeated at 9.30am the next day.
It has now asked ITV to attend a meeting on the issue. As a result of the broadcast, Ofcom also wants broadcasters who intend to transmit similar material to meet the watchdog to discuss whether it complies with the broadcasting code.
Viewers complained that the material should not have been on "a family show", and that the raunchy content was "too sexually explicit and inappropriate for the young audience".
But ITV said that burlesque routines had become "almost mainstream" and that it had used certain camera angles and wide shots to minimise potential offence following rehearsals.