Fergie will host the glam Life Ball in Vienna tonight. 

The pregnant singer is headlining the costume gala at the city's lavish City Hall to fight AIDS. 

Fergie added a twist, making the event a ball celebrating the dance form of voguing. A Life Ball plane reportedly left JFK on Friday packed with professional voguers, who "danced during the flight," according to Page Six of The New York Post.

Fergie took a different, more quiet flight to Vienna. 

"This will be her last trip before she gives birth. She wanted to get some rest before the ball," a source said.

The motto of last year's International AIDS Conference in Washington, D.C. - "Together we can end AIDS" - will be revived at the Life Ball 2013, as the most important global players in the fight against HIV and AIDS planned to attend. 

In a show of solidarity, Bill Clinton, 42nd President of the United States and Founder of the Clinton Foundation, Sir Elton John, Founder of the Elton John AIDS Foundation and Fergie, representative of amfAR - The Foundation for AIDS Research, will meet on the Red Ribbon stage at the event.

The 38-year-old Black Eyed Peas singer and husband actor Josh Duhamel, 40, are expecting their first child. The couple first met on Duhamel's TV show Las Vegas.

Duhamel and Fergie, birth name Stacy Ferguson, became engaged in December 2007. The two wed in January 2009.

Duhamel landed one of the starring roles alongside Oscar-nominated James Caan in the series Las Vegas in 2003. Duhamel became more recognized after he starred in the movie Transformers as Captain William Lennox in 2007 and the film Turistas in 2006 as Alex, garnering him more success.