The singer and rapper first began dating in 2016, while Aiko has a 13-year-old daughter called Namiko Love with singer O’Ryan.
On Saturday (2 July), the couple were photographed walking around Beverly Hills, with Aiko visibly pregnant.
Celebrating the news on Sunday (3 July) night, Aiko shared a photo to Instagram of her younger self holding her stomach.
The post was met with an outpouring of support from her fans, with one commenting: “So, so happy for you both and for the sweet being coming in to grace your lives - what a precious gift.”
“Congrats Pisces queen,” another fan wrote, while one comment read: “Jhene congrats I’m so happy for you mama.”
The news was also confirmed to People, with a representative telling the magazine: “The couple is overjoyed and looks forward to this next chapter.”
Speculation that the couple were expecting their first child together began last month after a fan tweeted that she’d spotted Aiko in Whole Foods looking “very pregnant”.
In 2020, Big Sean – real name Sean Anderson – released a track titled “Deep Reverence” where he rapped about Aiko having a miscarriage.
“Should be a billionaire based on the time off I’m not taking/ Probably why the s*** around me get crazy and we lost the baby,” he rapped.