We’ve all seen it—parents take a stroll on a hot summer day, and drape a blanket or a towel over the baby stroller to shield the tiny passenger from the sun.
But as temperatures across the U.S. and around the world continue to reach dangerous highs, pediatricians are warning that this simple practice could have very dangerous consequences.
Similar to a vehicle during the summer months, an enclosed stroller on a hot day can create a greenhouse effect on hot days in any enclosed space—including a stroller—despite using thin, free-flowing fabric covering that appears to be breathable. The result can be soaring temperatures.
“It gets extremely hot down in the pram, something like a thermos,” Swedish pediatrician Svante Norgren told Svenska Dagbladet, a Swedish newspaper in 2014.
“It would quickly become uncomfortable and potentially dangerous for the child.”
To test the theory, the newspaper set an empty stroller out in the sun on a hot day. Without any coverings, the temperature inside the stroller reached about 71 degrees. When they added a thin cover, the temperature skyrocketed to 93 degrees in just 30 minutes. And after an hour of being covered in the sun, the stroller approached 99 degrees.
The results of the experiment didn’t surprise Dr. Wendy Sue Swanson, a Seattle pediatrician who writes the Seattle Mama Doc blog. She urged parents not to panic, and instead, proceed with caution.
“Let’s not be crazy about this,” Swanson said. “For a hundred years, parents have been draping blankets carefully and safely over their baby strollers to protect them from the sun, and we still want them to do that. But we can be thoughtful about it and this is a good reminder.”
The bigger issue fueling the heat is that even a light covering over a stroller, cuts off all circulation of the air. Babies cannot regulate their body temperature, and tend to get very hot, very quickly. By stopping air flow within the stroller, you’re just creating more heat.
While it is possible for babies to have heat stroke, it’s unlikely to happen in this scenario when the baby is being monitored and checked in on throughout their time in the stroller.
Good ventilation is important for the comfort and safety of the baby, so experts suggest finding different alternatives to stroller coverings on hot days like finding shade, creating your own with an umbrella, or using a stroller with a canopy and an opening at the back to allow air flow.
In addition to that, doctors recommend checking on your baby every 10-15 minutes while in the stroller. If their cheeks are flush, they’re sweating, or they’re warm to the touch, it’s a good idea to take them out and give them some cooler air.