Seoul -As a first time parent it can be hard to know what is an overreaction when a baby hurts themselves, especially if they knock their head.

But for one South Korean family who had been holidaying in San Francisco in 2016, the decision to ring 911 and make short visit to hospital after their baby hit their head has resulted in a hospital bill totalling more than $25,000, South China Morning Post reports.

Jang Yeo-im’s eight-month-old son Park Jeong-whan fell off the bed in their hotel room on the first day of their trip, and while there was no bleeding on the boy’s head he was inconsolable. The concerned parents called 911 and the baby was taken to the Zuckerberg San Francisco General Hospital by ambulance.

During their short visit to the facility, reportedly only three hours and 22 minutes long, the infant had some formula and a nap and was discharged, after doctors determined he was fine.

The staggering $25,351 bill for the hospital visit arrived two years later.

Of that number, $21,084 of the total was for “trauma activation”.

“It’s a huge amount of money for my family,” Jang told the South China Morning Post.

According to the South China Morning Post, the family had taken out travel insurance but it would only cover about $6700.

“If my baby got special treatment, OK. That would be OK. But he didn’t. So why should I have to pay the bill? They did nothing for my son,” the mother said.

It is reported that a trauma fee is an amount charged by a trauma centre when medical professionals are assembled to see a patient in the emergency room who might have significant injuries. The amount is reportedly added on top of emergency room physician, facility and equipment charges.

These fees vary between facilities in the US but centres claim they are needed to have staff rostered around the clock who can respond to emergencies.

While the baby in this instance did not require some services in hospital, SFGH spokesman Brent Andrew defended the fee.

“We are the trauma centre for a very large, very densely populated area. We deal with so many traumas in this city – car accidents, mass shootings, multiple vehicle collisions,” Mr Andrew said.

“It’s expensive to prepare for that.”