Lady Antebellum brought their new brand spanking new single 'Downtown' to 'The Tonight Show With Jay Leno' on Jan. 29, closing out the show after midnight. The threesome, who will headline the Taste of Country Festival this June, delivered the upbeat, uptempo and undeniably catchy song flawlessly via the late night platform.

Singer Hillary Scott -- who is visibly pregnant with her first child -- looked beautiful and glowed like you'd expect a mom-to-be to glow. Dressed head-to-toe in black, Scott was animated and expressive with her eyes as she belted out the song's sometimes sassy lyrics.

Her bandmate Charles Kelley was going off on his tambourine during the performance of the song, which sounds like a surefire hit to us.

Host Jay Leno came to the stage to shake the trio's hands post-performance and to thank them for returning to his stage once again. He also kept referring to them as "Lady Auntie Bellum" whenever he used their name. It was sorta cute, since he placed the emphasis on a different syllable.

Even though Scott is preparing for motherhood, it's business as usual for Lady A, and they're not missing a beat or losing a step while she takes this next huge step in her life. We're left to wonder if her baby-to-be was dancing in utero to this crazy catchy new Lady A song. It's that resonant!

Watch Lady Antebellum Perform 'Downtown' on 'The Tonight Show'

WNBC 01-29-2013 00.32.10 from Darlene Hassett on Vimeo.