Iskra Lawrence Recalls 'Really Scary' Moment Seeing 'Lifeless Blue Body' of Son After Home Birth

"He wasn't breathing for two or three seconds," says Iskra Lawrence's boyfriend Philip Payne of their son's first moments after birth

It took Iskra Lawrence a little while to recover, both mentally and physically, from her first time giving birth — but she'd do it again in a heartbeat.

The British model, 29, and boyfriend Philip Payne announced the arrival of their first child, a son, on April 19. And now, they're sharing details about how the home-birth process (both the good parts and the scarier parts, like the "the most intense pain of [her] entire life") went down.

"I just had no idea how bad the contractions were," said Lawrence of the "primal" experience in a new vlog, sharing photos from the birth to Instagram. "I imagined the ring of fire, when the baby is crowning. I imagined, 'Oh, that's the really painful bit.' But no — for me the contractions were worse, in a way, because they just felt never-ending."

The first-time mom endured 12 hours of contractions, as well as uncomfortable side effects like "vomiting" and "diarrhea," before her water broke — at which point, surrounded by Payne and her parents, she got straight into her home birthing tub, to immense relief.

But once her midwife Ellie determined Lawrence's cervix hadn't dilated past 7 centimeters, she had to "pull" it further along manually — at which point the baby's head emerged.

The next part didn't go exactly as Lawrence had heard it would, with the baby coming out easily once the head was out. Instead, the Aerie model dropped into the "deepest squat I've ever done ... and [Ellie] just yanked him out."

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Iskra Lawrence and Philip Payne. Iskra Lawrence/ Instagram

Once the newborn was out, "He wasn't breathing for two or three seconds," said Payne.

"When you look back and you just see a lifeless, blue body ... that was really scary," Lawrence recalled. But once her son got oxygen and the couple heard his cries, they breathed huge sighs of relief.

"It all happened so quick that it wasn't traumatizing," she said. "I couldn't even take in what was happening 'cause [Ellie] just dealt with it. She was like, 'I know what exactly I'm doing, there's nothing scary here, we've got this.' "

Lawrence called the moment her midwife pulled out her placenta "a lovely relief" and "the best feeling in the world" — and instead of eating it, she planted it in the garden at their home. "It's very nourishing, so we've got two trees growing from the placenta," she said.

Iskra Lawrence planting her placenta. Iskra Lawrence/ Youtube

Iskra Lawrence and Philip Payne with son. Iskra Lawrence/ Youtube

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The new mom "healed very quick" and didn't tear during the experience, sharing that she went on to start working out two weeks after giving birth and had stopped bleeding completely by three weeks postpartum.

And though she jokes that she "nearly tapped out" during the process, "fast-forward only two days later" and she said she would "absolutely" do it again.

"There's something in nature that protects you from remembering the vividness of the pain. You would never do it again if you kept on reliving the pain, 'cause there's really nothing like it," Lawrence said.

"It just showed so much strength and so much resilience," Payne praised his girlfriend earlier in the clip. "You just kept through it and fought through it. I was looking at you and I was like, 'Wow. This is superhuman.' "