The rapper also explained how her years of stripping -- and her killer personality -- helped her get to where she is today. Later on, Cardi told Ellen that Offset already picked out their baby's name, which prompted Ellen to try and guess what it could be -- and no, it's not Susan. The dynamic duo then played an epic game of "5 Second Rule."
Here's everything you need to know:
Twerking at Coachella
Ellen played footage of Cardi's epic Coachella performance, where she twerked, dropped it low and did everything she learned prior to getting pregnant.
"It looks like you're getting ready to give birth right there," Ellen said about one of Cardi's dance moves.
"I was trying to show the world how I got pregnant in the first place," Cardi explained. "Like that. Like that. That's how it happened. That's why I'm pregnant."
"That's great," Ellen replied. "We were all curious, and we didn't know how, and now we do! So that's great."
Cardi B, Meet Cardi E
After going back and forth about the origin of Cardi's name, Ellen asked the rapper if it was OK to call herself Cardi E.
"You know, Ellen, I trademarked my name," Cardi said. "I paid $2,000 for Cardi. Are you gonna pay $2,000?"
"Maybe," Ellen replied. "I don't know. If I pay $2,000, I can use Cardi E?"
"Well, can you pay me the $2,000?" Cardi asked.
Her 'SNL' Pregnancy Bombshell
Cardi told Ellen she was really "nervous" for her second performance on "SNL" because she knew she'd be revealing her pregnancy on live TV.
"I was nervous for my second performance," Cardi explained. "For my first performance, I was like, 'Party with Cardi, eyyyyy!' And then on my second one, I was sweating, my underarms started itching a little bit 'cause it's like, 'Oh, my God, the world's gonna know that I'm pregnant, oh, here we go -- opinions coming!'"
Not too long ago, Offset stopped by Ellen's show, and she helped him get a discount on a car.
"Cardi, all you have to do is tell me what you want," Ellen said. "He told me what he wanted, I made a call and I found him the car. So tell me, what kind of car do you want?"
Cardi told Ellen she wanted a red Lamborghini truck with "baby friendly" interior even though she doesn't drive or have a license.
"I am a professional passenger," she joked before thanking Ellen for her efforts in finding her her dream car.
"See, I need friends like you! All my friends just get me into fights and trouble," Cardi said.
Her Stripping Career
Cardi told Ellen that as a kid, she was very "disruptive" and that it was hard for her "not to tell jokes." She always wanted to "be an artist" but "gave up" on her dream because "music wasn't paying [her] bills." That's when she decided to give stripping a shot, which she did for "three, three-and-a-half years."
"Did you like it?" Ellen asked.
"Hell yeah," Cardi replied. "I did. A lot of people want me to be like, 'Oh, I hated it. I don't recommend it to nobody.' I don't recommend it to everybody because it's not for everybody, but it made me money, it paid my bills, it got me my own apartment, it got me my boob job, you know what I'm saying? I had about $20,000 and I was 20 years old."
Ellen then asked Cardi how she made the transition from stripper to rapper, and she explained that the money she made stripping she "invested" into her "dream."
Cardi said it was her "million followers on Instagram" and "personality" that "took [her] places."
Offset Named Their Baby
Cardi revealed that her fiancé already picked out the name of their baby.
"My dude named the baby," she said. "I really like the name."
When Ellen asked what it was, Cardi said she wanted to leave that up to Offset to announce since it was his choosing.
"I'm just gonna guess -- Susan? No? More complicated than that? Is it gonna be like a tricky name?" Ellen asked.
"It's like almost tricky, but when it comes out, it's like, 'Ahhhhh!'" Cardi said.
Ellen then offered her $20,000 to name the baby Ellen, to which Cardi replied, "Can I put it in the middle name?"
Cardi and Ellen then played a game of "5 Second Rule," where they were each given five seconds to name three things related to the topic they were given.
For example, Cardi was asked to name three things not to do at a strip club, to which she replied, "Not get money, slap the booty real hard and eat chicken wings." Ellen was then asked to name the last three celebrities she texted, to which she replied, "Bruno [Mars], Justin [Bieber] and Anna Faris." But when she was asked to name three things she wished she owned but doesn't, the comedian was completely stumped.