Britney SpearsBritney SpearsOops! It seems that Britney Spears has suffered a bit of a knock.

The princess of pop, who was once named sexiest celeb on the planet, hasn't even made it into this year's top 100.

Britters topped FHM's sexiest women in the world poll in 2004 and made it to no.6 in 2005.

But votes for the new mum have severely dropped off this year, leaving her stranded around 20 places outside the hot 100.

To have any chance of making it back onto the list, Britney would need around 20,000 more votes.

Britney fans have until midnight on 10 April to change all that.

FHM's editor Ross Brown said: "A couple of years ago, FHM readers couldn't get enough of Britney, and they unanimously agreed that she was by far the sexiest woman on the planet.

Britney SpearsBritney in pop mode"It's hard to believe that she's currently outside the top 100.

"I can only guess that a raft of less-than-flattering photographs and her general disappearance from our TVs and radios have left readers under the impression that Britney's lost her sex appeal."

* To vote, go to www.fhm.com/100sexiest.