"Our little man arrived! Jack Oscar Statham 8.8lbs on Saturday June 24th," she captioned a photo of his hand.
The couple, who met on the set of Transformers in 2011, took to Instagram in February to announce that they were expecting.
In the beachside snap, the model, 30, posed in a bikini with her hand on her hip and her baby bump on display.
“Very happy to share that Jason and I are expecting!” she captioned the snap, adding, “lots of love.”
As previously reported, the Furious 7 actor, 49, popped the question to his supermodel girlfriend of more than five years in January 2016. Shortly after, the British beauty debuted her $350,000 five-carat Neil Lane-designed engagement ring on the red carpet at the 2016 Golden Globe Awards.
The former Victoria’s Secret model opened up about her feelings on marriage and the importance of being in a healthy relationship to Self in April 2015, saying: "For any couple that's been together for a certain amount of time, there's a massive amount of pressure to get married," she said. "I totally believe in marriage, but being in a happy relationship is much more important to me."
"We're best mates," she went on to say. “He makes me laugh every day. I almost feel like I never had a proper boyfriend before!”
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