AceShowbiz - Oops! Christina Aguilera showed more than she originally intended. The former judge of "The Voice" had wardrobe malfunction while dancing her way into her own birthday party. The blonde star flashed her breast to a room full of people as she rang in her 39th birthday.

The "Burlesque" actress rocked a glittering red mini gown with a plunging neckline, a high ponytail, and black thigh-high boots. When her boob escaped her low neckline, she just nonchalantly adjusted it and even opened her dress herself to teasingly show off her breast once again.

"Entering the last year of my 30s with the best vibes," she wrote on Instagram. "Dancing, singing, salsa-ing. What a night. SO thankful for everyone in my life who's been on this journey with me. Who has stuck by me through and through. 'She came, she conquered. Get ready 2020.' "

The birthday girl added on Twitter, "This year, I have felt more inspired than ever. From #TheXTour and #TheXperience, to getting to meet and hug the fans, I feel grateful for the present and I'm looking forward to the future. 2020 is gonna be a big year... Who's coming with me."

The "Genie in a Bottle" hitmaker kicked off the night with a fancy dinner party with her family and friends before turning up the music. There were lap dance and naked man involved. Demi Lovato and boyfriend Austin Wilson were among the celebrity guests.

Xtina turned 39 years old on December 18. Before the party, she was surprised by her friend Gilbert Saldivar with a Mariachi performance by the swimming pool. "It's a Mexican tradition to be serenaded the night before your birthday.... So magical and amazing!" she gushed.