A pregnant Christina Aguilera took the stage yesterday at the Wango Tango concert in Los Angeles where she performed 'Say Something' with the band A Great Big World.

The 33-year-old singer looked radiant in a slightly sheer dress as she sang her heart out on stage despite being pregnant with her second child. 'Say Something' is the breakout hit from pop duo A Great Big World. The song initially was a solo single off band member Ian Axel's 2011 album 'This is the New Year' but was later re-recorded with Aguilera as a radio single when Axel formed A Great Big World with Chad Vaccarino. The song debuted at number 16 on the Billboard Hot 100 chart.

Aguilera revealed in March that she and fiance Matthew Rutler are expecting a baby girl. Aguilera is already mother to her six-year-old son, Max, with ex-husband Jordan Bratman.

We think Christina looks terrific and we can't wait to see what baby Xtina will bring to the world!

Kevin Winter, Getty Images