Nash Keen defied incredible odds to make it to his first birthday and now he is a record holder, officially named the world’s most premature baby.

The tiny fighter, who his parents affectionately call ‘Nash Potato’, was born at 21 weeks, weighing just 283 grams and 24cm long.

No other baby has ever survived being born so early and Nash now holds the Guinness World Record, taking the title previously held by Curtis Means, who was born at 21 weeks and 1 day.

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Nash had to be resuscitated when he was born July 5, 2024 and spent 189 days in hospital.

His mother Mollie Keen said the past 12 months had been “surreal”.

“It feels surreal, honestly. A year ago, we weren’t sure what the future would look like, and now we’ve celebrated his first birthday, she told Guinness World Records.

“It’s emotional in so many ways: pride, gratitude, even some grief for how different his journey has been. But above all, it feels like a victory.”

She continued, “Nash isn’t just a record breaker – he’s a heart-stealer. From the very beginning, our family and friends rallied behind him, and as his story spread, so did the love.”

Ms Keen and husband Randall marked Nash’s milestone with a birthday party attended by family and close friends in Ankeny, Iowa.

While pregnant, Ms Keen was diagnosed with an incompetent cervix, which meant it could dilate prematurely, and had a preventative stitch in a bid to keep Nash in the womb.

But it had to be removed when she was rushed to hospital at 20 weeks when contractions started.

Patrick McNamara, the director of neonatology at University of Iowa’s Stead Family Children’s Hospital, told Iowa Public Radio he was “incredibly blunt” with Nash’s parents.

“I told them the survival chance was zero, because no one had ever survived at 21-plus-zero. So, by the laws of life, there has not been a survivor. However, we would do everything we could in our power to change that paradigm.”

After a shaky start where Nash had to be resuscitated and had a breathing tube, his heart rate and oxygen levels stabilised, giving hope he could survive. Doctors credited advanced ultrasound technology that helped care for Nash and identify any early health issues.

“People come from all across the world to learn how we take care of extremely preterm babies and how we use hemodynamics to provide better information to understand what’s going wrong with these babies,” Dr McNamara said.

Nash was diagnosed with chronic pulmonary hypertension and mild permanent hearing loss. And, while he still returns to the hospital for appointments, the amount of oxygen treatment Nash needs is falling and he could come off it soon.

“He’s so full of personality,” Ms Keen said. “He’s happy. He kicks his legs all the time. He might be a little delayed in some milestones, but I expect him, by maybe 2 or even just before Kindergarten, that he’ll be right alongside his peers. It’s really a joy to see how far he’s come.”