Milaois Murphy was shocked to discover to give birth to a 1lb baby, without even realizing she was expecting.

A Dublin teen thought her unexplained pain and vomiting were appendicitis, and couldn't understand her weight gain.

It wasn't until Murphy's waters broke that her family could comprehend what was happening.

The 18-year-old delivered her baby, who was more than three months premature, in the kitchen.

She told the Irish Mirror that she had been up all night at home sick and had experienced back pain, leading her mother Victoria to think she had appendicitis.

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Murphy said she has "no idea" she was pregnant until baby Harper was "born on the kitchen floor" at the family's home near the Phoenix Park.

“When she came out she let out a little cry and then she stopped breathing so me Ma had to resuscitate her," Murphy told the Irish Mirror. 

The baby weighed a mere 1lb (458g) when she was born 26 weeks into the pregnancy, and she stopped breathing almost immediately. Newborns usually weigh around 7lbs.

“The baby was only the same size as her hand. She was just a pound. If it wasn’t for her, she is a super Mammy. I think the ambulance men were telling her how to do it," Murphy said of her mother Victoria.

“The ambulance and the fire brigade were just amazing. They did kind of scare me a little bit when they said they had to put the baby in a plastic bag to keep her warm.

“At that time, I didn’t even know what I had. I had so much adrenaline going around my body, I didn’t feel pain anymore.”

Murphy maintained that she was in so much shock, she didn't even realize that she had given birth.

Consultant Neonatologist Adrienne Foran said, “Harper was smaller than a bag of sugar. She was about 20 minutes old when I met her, she had come in with no heart rate but responded well to initial resuscitation.

Murphy and her partner James Mulligan appeared on RTE's recent show The Rotunda, as they shared Harper's journey. The baby, who is now five months old and weighs a healthy 8lbs (3.6kg), endured two laser eye surgeries during her time in the ICU.

Murphy is taking time out from school to care for her newborn, but plans to return to education next year to take her Leaving Certificate (final school exams).

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Surprised parents Milaois Murphy and James MulliganInstagram.com/Milaois_15