Is it safe to cover your baby's pram with a blanket in hot weather?

So, if you’re taking your baby out in a pushchair on a hot, sunny day, it’s sensible to make sure your pram is covered – preferably with an in-built sunshade (if your pram has one) or a light, well-ventilated, attachable one.

If you find yourself caught short in the sun without a shade, a light covering, like a muslin, is better than nothing at all or than just the pram hood.

But it’s important to know that:

• you should check your baby regularly to make sure they’re not getting too hot
• once you’re in the shade, you should remove the pram covering
• a stationary pushchair in the sun (covered or uncovered) seems to heat up to higher temperatures that one that is being pushed around.

But what about all the scary stories saying you shouldn’t cover your pram with a blanket?

Yes, there have been plenty but we now think they don’t tell the whole story – and they could be confusing us all in the process.

It all started a few years ago when dozens of newspapers and websites, including – hands up – MadeForMums, picked up on a Swedish report about how hot a baby’s pram can get when it’s covered with a blanket or towel on a hot day.

Given what the report said – especially the warning it contained from a paediatrician about the potentially fatal consequences of a baby overheating – it seemed important to warn parents of the potential dangers of covering your pram with a blanket on sunny days.

That’s because overheating is a very real concern. Babies can’t control their body temperature as well as adults can, and overheating can lead to heat rash, restlessness and in extreme (though rare) cases, SIDS (sudden infant death syndrome).

But when we realised the confusion and worry this story was causing among parents (ourselves included), we decided to try to look into it all more deeply.

We spoke to experts and even conducted our own pram experiment in hot sun. We wanted to test the scary headlines and try to find out what the real facts are – so that we can all be clearer about the safest thing to do when we need to take our baby out in the sun.

Right, so how did all the scare stories start?

Five years ago, a Swedish newspaper carried an article in which a reporter had recorded the soaring temperatures inside a pram that was covered by a blanket – and asked a paediatrician to comment on the risks to a baby left in a pram that was this hot.

The pram was left out in the sun on a warm day and recorded that it reached an internal temperature of 22 °C. But when a 'thin cover' was placed over the same pram for 30 minutes, the temperature inside the pram rose significantly – to 34 °C. And, after an hour, it had risen again to 37 °C.

It's important to note that the reporters weren't academic researchers, and this wasn't a 'proper' scientific experiment.

Pic: Getty image

However, the newspaper showed their findings to Svante Norgren, a paediatrician at the Astrid Lindgren children's hospital in Stockholm, and she said, "It gets extremely hot down in the pram, something like a thermos.

“If a child gets too hot, then the child may think that it is back in the womb, which is why breathing may stop.”

The paper then reported Svante as saying that “the best bet for parents is to abandon the practice of using towels or thin blankets as a cover and instead place the pram in the shade”.

Experts at both the Lullaby Trust (which provides advice on safer baby sleep) and at the Royal College of Midwives both commented that covering a pram with a blanket on a hot day could be dangerous. "Covering a pram or buggy with a blanket could lead to overheating, which increases the chance of SIDS," said Lucy McKeown of the Lullaby Trust.

So why is this confusing parents?

The Swedish report – which so many UK newspapers and websites picked up on – focused so strongly on the dangers of covering your pram with a towel or blanket in hot weather that lots of people thought it might be safer NOT to cover your pram at all when it’s hot and sunny outside.

But this, obviously, means you risk leaving your baby exposed to sunburn and skin damage from UV rays. Indeed Cara Sayer, founder of the pram-shade accessory company SnoozeShade, told us she's fearful that the 'blanket danger story' has been shared so much over the last few years, that parents have become afraid of protecting their child from the sun.

"What I am worried about," she says, "is that parents will choose to leave their baby uncovered in the sun because they have been scared so much by… this story.”

It’s important to note that neither the Lullaby Trust nor the Royal College of Midwives said we should stop covering prams altogether.

The Lullaby Trust recommends attaching a mesh air-permeable pram shade, clip-on sunshade or parasol to a pram or buggy, if you're out in hot weather. And the Royal College of Midwives suggests investing in a pushchair with a large hood that can provide both shade and ventilation

But this leads to a 2nd confusion for parents: is it OK to put a very light cover, like a muslin (which most parents have handy) over your baby’s pram on a hot day to give them some protection from the glaring heat and UV rays if you’re not within easy reach of any shade (or if you’re walking in the sun to get to a shaded spot)? Is that safer than no cover at all?

Cutting through the confusion: the MadeForMums pram experiment

By doing our own experiment on how much hot weather heats up covered and uncovered pushchairs, we wanted to find out:

• Does covering a pram in hot weather make it heat up more than not covering it?
• Do some covers make a pram heat up more than others?
• Does keeping the pram stationary in the shade, stationary in the direct sun, or pushing it around in the sun make a difference to how much it heats up?

We carried out our experiment over 2 very hot (approximately 28 °C) days in July. On the first day of the experiment, we used 3 identical prams, and covered them with:

• a muslin
• a specially designed SnoozeShade pram cover
• nothing at all – apart from the pram hood

We then put the prams in 3 different settings:

• stationary in very hot, bright sun
• being pushed around in hot sun
• stationary in the shade

We placed a digital room thermometer in each pram (all the thermometers were identical) and checked how much the temperature rose in each pram after 15 minutes.

Pic: The prams stationary in the sun with (from left) no cover, a muslin and a SnoozeShade and (inset) the shadows show how high and bright the sun was

On the second day of testing we carried out exactly the same experiment using:

• a cellular blanket
• a thick, good-quality wool blanket.

Important things to note about our experiment are:

1) We are not scientists but we are investigative journalists and were keen to carry out our testing as thoroughly as possible

2) We carried the experiment out on 2 separate days. Although the weather was similar, conditions were not exactly the same

3) We did not use real babies for this experiment

4) We only checked how much temperatures rose for 15 minutes

We used exactly the same pram for each of the covers, and the same thermometer, and meticulously noted our results in terms of how much temperature rose.

What did we find? The results

What happened when the pram was…

• stationary and in direct sun: Our experiment showed that when the buggy was stationary in direct sun, the SnoozeShade kept the pram temperature lowest, and using no cover at all made the inside pram temperature rise the most.
• being pushed about in hot sun: When we walked with the prams, again, all the prams with covers stayed cooler than the pram which had no cover at all. We actually found using a muslin kept the temperature lowest out of all the covers. We think that the motion of the pram and the slight breeze that day made the muslin flutter and so allow some air flow into the pram.
• stationary and in the shade: We found the inside pram temperature rose very slightly when covered compared to not being covered.

Pics (from left): Day 2 of the experiment: a pram in the sun with a thick woollen blanket; a pram in the sun with cellular blanket; Reviews Editor Hazelann walks in the hot sun with one of the prams

What do the experts say?

We spoke to a leading thermophysicist who told us that babies naturally get hot – for example, when they eat they generate a “heat load” which they need to lose all the time (through breathing and cooling from the air).

But because their thermoregulation (their ability to maintain a stable body temperature) is poor, they can overheat easily.

If a baby is exposed to direct sunlight on a hot day their heat load will increase by far more than they would naturally by, say, eating, so putting them at much more risk of overheating – which is why it’s a very good idea to make sure they’re shielded from the hot sun (as well as to protect them from UV rays).

But at the same time, covering your pram will mean the air flow will also be restricted to some extent (making it harder for your baby to lose heat) – so, basically, it’s a bit of a balancing act.

So what should I do when I’m out with my baby in the pram on a hot day?

The thermophysicist’s advice and the results from our experiment both suggest that if you’re in direct sun with your baby in a pram, you should seek to shade your child.

The scary stories that suggest you should never cover your pram fail to mention that it’s actually worse for your baby to have no barrier from the sun.

If you don’t have an in-built pram shade or a pram-shade accessory and you’re in a place where you can’t get to shade quickly or easily, covering your pram for a short amount time with a light blanket or muslin while you seek shade is better than leaving nothing between your baby and the heat of the sun.

The bottom line

It’s never a good idea to expose babies to direct hot sunlight as their bodies can so easily overheat. Plus, the sun’s rays can cause UV damage to your baby’s skin which could lead to sunburn and heighten the risk of skin cancer in later life.

Every pram, covered or not, will heat up when it’s outside on a hot day but there does seem to be expert concern that covering a pram with a blanket can heat it up significantly – in a way that could be dangerous for a baby.

And while a muslin is clearly a better option, especially if it's loosely draped, there is still some risk of overheating – though it’s probably still more sensible to drape over a loose muslin or very light blanket to keep your baby's skin safe than to leave the pram uncovered. Though you shouldn't do this for any extended amount of time and you should be very aware of the overheating dangers.

Ultimately, if you're going to be out and about with your baby in a pram in hot weather a lot, you should seriously think about getting a pram with a large inbuilt sunshade or buying an attachable, ventilated pram shade that covers your pram properly.

If you manage to find a shady spot, there might be a temptation to cover your pram to keep out light or avoid distractions to help your baby sleep.

But our experiment suggested that covering your pram in the shade – particularly with a fixed cover that doesn’t have any room for air to get in at the bottom – actually increased the inside temperature of the pram slightly. So we think it would be wise to remove your pram shade, once your pram is stationary in a shaded spot.

Above all, keep a very close eye on your baby if you’re out on a hot day: nothing can substitute for checking on them regularly.

We've got 10 of the best pram shades right here

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