Sarah Michelle Gellar found fame in Buffy the Vampire Slayer

The complaints made by the Parent TV Council and the Americans for Decency group were rejected because the shows did not violate FCC indecency rules.

Characters Buffy and Spike were shown having sex in a 2001 episode.

But the FCC said there was "little evidence that the activity depicted was dwelled upon".

The Commission concluded that the Buffy episode was not sufficiently explicit or graphic to be indecent and that the sex was not used "to pander, titillate or shock the audience".

Indecency crackdown

The PTC made the complaint about the Buffy episode, while Americans for Decency took issue with a Will and Grace episode which aired in March last year.

The complaint related to a scene where two women simulated having sex, but the FCC found the scene was not "patently offensive" under its indecency regulations.

As in the Buffy case, the Commission also concluded that the activity depicted was not "dwelled upon, or used to pander, titillate or shock the audience".

The US Senate recently backed increased fines for airing indecent material.

Under the new measures, the maximum fine would increase to as much as $275,000 (�151,000) for each indecent incident.

The fines would keep increasing per incident until a maximum fine of $3m (�1,649,440) a day was reached.

The issue of indecency on US radio and television has been a major talking point since pop star Janet Jackson exposed her breast on live TV during the Superbowl transmission in February.

The incident generated more than 500,000 complaints to the Federal Complaints Commission (FCC).