The rapper came out alongside the host as the show opened, rocking a gold satin ensemble that clearly showed off her sizable baby bump, and throughout the night she was very candid about her pregnancy, including a particularly inspiring remark about the effect her forthcoming progeny has had on her outlook.
"I don't know if it's the strength of the fetus, but I have never felt so hungry to succeed," she said, eliciting an enormous cheer from the audience.
The singer also said that, after hiding her pregnancy for months, she would have continued to keep it secret up until she gave birth if she had the option.
"And I could have gotten away with it if it wasn't for that meddling paparazzi!" she said, doing her best impression of every Scooby-Doo villain.
It was a night of fun games and wonderfully awkward moments -- including the performer explaining the nuances of her many inexplicable vocalizations that she's become famous for, a particularly dirty installment of the long-running segment "Box of Lies," and a gloriously bizarre interview with comedian John Mulaney.
One of the night's biggest musical highlights came when Cardi closed the episode out with a TV debut of her new single, "Money Bag."
Rocking a skin-tight black latex body suit with black fishnets and a super-short blonde pixie-styled wig, the gold chain-draped rapper blew the roof off the studio, with a little help from The Roots.
Before her time as co-host, the "Bodak Yellow" singer last appeared on the Tonight Show back in December, one of three appearances she's made on the show.
Hours before the episode aired, the show released "a brief message" from Cardi on Twitter, as she sat behind Jimmy's desk.
"Things are going to be just a little bit different, so stay tuned and watch tonight's show," Cardi gleefully teased in the brief clip. "I'm so excited!"
Cardi was greeted with a round of applause backstage after her big reveal, where she flaunted her sizeable bump in a curve-hugging white gown. In an Instagram video of the excited celebration, a beaming Cardi exclaims "I'm finally free!"