A video showing rows of babies sleeping in prams in public has captured widespread attention — because they're all alone with parents nowhere to be seen.
But in Denmark, it's common practice for infants to be left alone in the street while they nap, and the concept is blowing people's minds.
"Denmark: Where babies sleep outside alone," an American woman captioned a video on TikTok which has since garnered over 11 million views.
The mum of four, who lives in the Scandinavian country, shared a compilation of clips showing prams parked under trees, on footpaths and outside shops, which is common behaviour.
It's not just Denmark where the phenomenon is widespread. Other Nordic countries in northern Europe have adopted the practice too.
"Finland here, our babies sleep outside just like that. Also during the wintertime (wrapped in warm clothes ofc)," one person said in the comments.
"Same in Sweden. Some of our preschools even let the kids sleep outside," another added.
Why do babies sleep outside in Denmark?
There are a few reasons why, Dr Timothy Heffernan, an expert in Icelandic culture and Scandinavian societies at UNSW, told Yahoo News Australia.
"It's a cultural norm that all babies go through during infancy and it's common to see prams outside houses and throughout the city, especially at coffee houses," he said.
"Not only does it help babies to fall and remain asleep during the day, but it also helps to fully acclimatise babies to the cold weather, which is important in [Nordic countries]."
Some experts believe there are a number of health benefits associated with sleeping in the fresh air with nurses and midwives in northern Europe often encouraging it.
But Associate Professor Dr Nina Sivertsen said this is more "evidence-based" and there is "no real research to back it up" although "many Nordic mothers swear by it".
Building 'design structure' another reason for prams outside
"No one really knows" when the tradition started, "perhaps back when we had no other options," Dr Sivertsen, a senior lecturer at the Flinders University and the Arctic University in Norway, guessed.
But Dr Heffernan, a Postdoctoral Fellow at UNSW School of Built Environment, said there are also "a number of design factors for why prams are left outside."
"In Iceland [and other Nordic countries], large prams are common, similar to those of the early to mid 20th century, with large, open tops that are covered by blankets," he explained.
Many buildings were built 80-100 years ago, and coffee houses are often in older buildings, Dr Heffernan pointed out, adding prams "don't easily fit inside."
"Similarly, prams are usually stored in apartment entryways because they don't fit inside the living quarters of people's houses very easily," he said.
"So, it isn't a stretch for parents to lay their sleeping baby outside, within view of the people in the house."
Fears for babies getting kidnapped or sick
Naturally, people were quick to question the potential dangers of the practise with fears of kidnapping and even hypothermia among the common, and valid, concerns.
In Denmark, the average temperature of January and February just above freezing at zero degree celsius, but further north can see temperatures of below -20°C. So one "does have to take precautions," Dr Sivertsen said.
"During winter babies always wear layers of wool clothing and sleep in down/feather-filled sleeping bags on top of sheepskin wool mattresses," she explained.
"And mothers take care to follow safe sleep advise (sleeping on back, no soft toys, using pram harness to secure babies."
While there are "no set childcare policies about sleeping babies outside" the health department states that "one should not sleep babies outside below minus 10 degrees".
Some parents put thermometers inside their child's pram to ensure it's warm enough. While others almost always include a monitor so they can keep an eye on them.
Culture clash: 'I am shocked'
Some TikTok users couldn't help but draw comparisons to their own countries with one saying they were "shocked" such a thing existed.
"I'm from South Africa, and it's a huge NO. Not safe....," one said.
"The fact I can’t imagine feeling that level of safety is so sad," shared another
Another person from the United State said "we would get arrested if we did that here." And it's true.
In 1997, a Danish mother, was arrested in New York City for leaving her baby outside a restaurant.
She was later charged with child endangerment and spent 36 hours in jail, according to the New York Post. But the charges were eventually dropped.
But one person replied to say "Denmark is a very expensive country."
"Believe me, we don't want anyone's children," they added.
Security 'rarely a concern' in these countries
Dr Heffernan said "security is rarely a concern," in Nordic countries, and as the video shows, "it is very common to see prams clustered together – indicating groups of parents are socialising nearby".
Dr Sivertsen agrees and said visitors "often worry about safety" with many often asking 'what if someone takes the baby.' But like in Iceland and Denmark,"Norway is a very safe country," she said.
"Most of us agree that we all have to trust each other. But as a rule of thumb, one should always be able to see the baby and check on them regularly," she added.
Why leaving prams outside would never work in Australia
As for Australia, Dr Heffernan agreed that "unattended prams would pose more of a safety concern" and there are a few reasons for this.
"In Iceland and across the Nordic countries, there is less of a concern and perhaps less societal regulation over children in public. Freedom to move around and enjoy public and natural spaces are prioritised in these countries," he said.
"Australia's larger, more diverse population and its societal regulation over children in public mean that the same practice is unlikely to occur here — as there hasn't been a history of this practice, nor do parents appear to be embracing it in any significant way."
What's more, prams fit easily on public transport, in buildings and within houses in Australia.
Also, the warmer weather means it's not always appropriate to leave children unattended in prams, for instance on hot summer days, Dr Heffernan pointed out.
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