The pregnancy news first broke back in April, when a source told US news outlet Entertainment Tonight that the couple were trying to keep the pregnancy news quiet.
"Gigi and Zayn are expecting their first child together and the couple is very excited!" the source said at the time.
"Gigi has kept the secret close to her family and friends for a while as she’s only a few months along. Once Gigi and Zayn got back together at the end of last year it was like they never skipped a beat and knew what they had was special. The couple and their families are overjoyed."
The 25-year-old model first confirmed the news herself during an interview on the Tonight Show with Jimmy Fallon in late April.
"Thank you so much!" she said when Fallon congratulated her on the pregnancy.
"Obviously, you know, we wish we could’ve announced it on our own terms, but we’re very excited and happy and grateful for everyone’s well-wishes and support.
When asked how she was coping, Gigi says she was trying to be present for every part of the journey.
"Especially during this time, it’s a nice silver lining to be able to be home and together and really experience it,” she revealed.
As for any pregnancy cravings, she revealed she has become obsessed with bagels.
"My craving has been everything bagels," she told Fallon.
"I eat an everything bagel everyday and so I was already like, so excited that my birthday cake was the everything bagel."
Gigi and Zayn, 27, first started dating in late 2015 and briefly split in 2019, before rekindling their romance.
Gigi is the daughter of Real Housewives star Yolanda Hadid and her husband Mohamed.
She's also the sister of fellow model Bella and brother Anwar, who is dating pop singer Dua Lipa.