An American baby born at just 21 weeks of pregnancy has officially been recognized by Guinness World Records as the world’s most premature surviving baby after celebrating his first birthday.

Born 133 days early, weighing less than 0.3kg

According to ABC News, baby Nash Keen was born on July 5 at the University of Iowa Health Care Stead Family Children’s Hospital in Iowa City, Iowa, at just 21 weeks of gestation—133 days before his due date.

At birth, he weighed only 10 ounces (about 0.3kg) and measured just 24cm long.

A full-term pregnancy typically lasts around 40 weeks. Babies born before 37 weeks are considered premature, while those born before 26 weeks are classified as micro-preemies.

Nash’s case went far beyond that threshold, arriving shortly after reaching 21 weeks of gestation—a stage at which many medical teams around the world do not typically provide intensive intervention because the chances of survival are considered extremely low.

Dr. Patrick McNamara, who cared for Nash, told KCRG: “Based on the available medical data, I had to tell the Keen family that the chances of survival were essentially zero. Yet despite every obstacle, Nash not only made it through but has now celebrated his first birthday with his family.”

Earlier this year, after spending six months in the hospital, Nash was well enough to go home to Ankeny, Iowa.

According to The Guardian, this was the second premature birth for Nash’s mother, Mollie Keen. She had previously lost a baby girl at 18 weeks of pregnancy. During this pregnancy, she and her husband were excited but remained cautious.

“We were thrilled to be expecting, but we didn’t let ourselves hope too much,” Mollie said.

At 20 weeks, doctors discovered that her cervix had already dilated by 2cm, a sign that early labor could begin at any time.

According to The Independent, with medical support, the pregnancy was safely extended until exactly 21 weeks—the earliest gestational age at which life-saving care is routinely offered in the United States. Nash was born shortly afterward, becoming one of the earliest surviving premature babies in modern medical history.

Dr. Malinda Schaefer, who delivered Nash, described the birth as “a new frontier in maternal and neonatal medicine.”

According to GuinnessWorldRecords.com, Nash was immediately admitted to the Neonatal Intensive Care Unit (NICU), where he received round-the-clock monitoring and a series of specialized treatments.

Dr. Amy Stanford, one of the physicians who cared for him, said: “Nash faced many significant challenges from the very beginning, but he showed extraordinary resilience. After those incredibly delicate first weeks, he began making steady progress, which was truly remarkable.”

Nash still uses supplemental oxygen and receives nutrition through a feeding tube, although he is preparing to begin eating pureed foods. He is not crawling yet, but he can roll over and is practicing standing on both legs.

According to his parents, Nash is energetic, determined, and always smiling.

“Nash is a very determined little boy. He’s curious, full of joy, and never lets his early journey define him,” his mother told The Independent.

His father, Randall, added: “One day Nash will be able to say, ‘I entered this world fighting, and I’ll keep moving forward with that same determination.’”

He also shared that whenever they call him “Nash Potato” or cheer him on while he practices standing, Nash lights up with a big smile and tries even harder.

Guinness World Records has officially recognized Nash as the world’s most premature surviving baby, surpassing the previous record held by Curtis Means of the United States.

Nash celebrated his first birthday with a small gathering of family and close friends. He received educational toys, new clothes, diapers, and, most importantly, his official Guinness World Records certificate.

“Waking up and seeing him every morning is the greatest gift we could ever ask for,” Mollie said.