Australian fitness model Chontel Duncan — who is best known for her rock-hard pregnancy abs — documented her famous tummy in weekly progression photos before the birth of her son last month. “OMG the changes in my bump from week 37 to to 39 is crazy,” the former Miss Universe finalist Instagrammed on April 12, alongside 12 black-and-white images taken by photographer Melanie Wilkes.

The 6-foot-1 social media sensation first grabbed headlines in November after posing stomach-to-stomach with her friend Nat, who was four weeks further along in her pregnancy. Addressing the difference in their belly sizes, Duncan noted: “Each woman carries differently, and this most certainly doesn’t mean one is doing something wrong or not healthy.” 

I should do a another collage like this post Little D... But wow the human body is amazing!!!!! 💙🍼👶🏾

A photo posted by 🇦🇺🇳🇿SnapChat 👻 ChontelDuncan (@chontelduncan) on

Duncan, 27, and her husband, Sam, welcomed their 7-pound, 13-ounce son Jeremiah on March 25. In an Instagram post, she raved that the baby was “extremely alert and very strong.” Just five days after giving birth, the trainer at HIIT gym shared a snap of herself in a neon orange bikini. The accompanying caption read, “I can’t believe my bump is gone.”

The new mom opened up about her body image to Elle. “I’m proud of how my body looks after baby,” she explained in an April 12 interview. “I think I may not have got ginormous hips, I may not have got crazy stretch marks, but my body still went through a pregnancy.”

Duncan — who was kickboxing and doing plate pushes at 37 weeks pregnant — also hit back at online trolls who criticized her intense workout regimen. “It’s become so taboo if you do anything that looks vigorous when you’re pregnant,” she said. “These babies are so supported that the doctors are more afraid of us hurting ourselves holding the extra load of weight on our bellies and our backs … There are a lot of misconceptions that these babies are super fragile in our womb.”

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