The mum-to-be has now confirmed the news, while also explaining why they chose to keep their wedding a secret.
'There are so many moments that I share with the world and then there are moments that I want to keep for myself! "Getting married was one of those moments!" she wrote.
Despite the fact that Cardi and Offset were already married, the Migos rapped proposed to Cardi on stage in October, popping the question at Power 99's Powerhouse concert in Philadelphia. Cardi noted that the proposal was performed out of love and understanding that it was a special moment that every young girl would like to have.
Still, her engagement to the father of her child, the rapper Offset from the group Migos, seemed to be a public affair.
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"Was one morning in September we woke up and made a decision to get married", she continued.
It looks like Cardi and Offset purposefully let this slip so that her fans would finally know that she wasn't having a baby out of wedlock.
Word on the street has is it that the couple is expecting a baby girl.
Read her full post below. There just wasn't enough time, according to TMZ, because Offset woke up one morning and asked Cardi B for her hand, and by the end of the day they were married, with only an officiant and Cardi's cousin present. "You should thank yours".
The couple still plans to Wednesday in an official ceremony once Cardi gives birth next month.
Cardi B, whose real name is Belcalis Almanzar, rose to fame past year with the song Bodak Yellow while her current single, I Like It, is a contender for 2018's song of the summer. "She's real. I wanted real".