How to help your baby sleep safely in hot weather

We all find it hard to sleep at night when it’s hot outside, but it can be especially difficult for babies and young children. If your baby is too hot, they are likely to feel uncomfortable, they may get heat rash and their sleep may suffer. Your baby may wake up more regularly in the night than normal, or they may be more upset or fussy.

The ideal temperature of a baby’s room should be 16 to 20C, according to the Lullaby Trust.

When your child’s body temperature is too high, they may sweat excessively and lose fluids, leading to dehydration. Symptoms include lack of tears, a decrease in wet nappies and they may be lethargic. Overheating has also been linked to SIDS, Sudden Infant Death Syndrome¹.

However, with some small changes to your baby’s environment and clothing, you can help prevent your child from getting too hot.

Tips and advice for keeping your baby cool at night

Check on your baby

If your baby is asleep, it’s tempting to leave them be in case they wake up. However, if it is very hot, it is always safer to check on them every so often to ensure they aren’t overheating.

If you’re unsure about how hot your baby is as they sleep, have a quick feel of their chest, hands and feet, as well as their forehead. If your baby feels sweaty and cold to the touch this is a sign that you need to adjust their clothing, bedding or the room temperature. Your baby’s skin should always be warm and dry to touch.

Jenny Ward, chief executive of The Lullaby Trust, a charity that promotes safe sleep for babies, says: “We’ve had lots of enquiries from parents on social media who are worried about their babies overheating, and we appreciate how hard it can be to keep babies cool in such hot weather.

“We would recommend parents regularly monitor their baby’s temperature. If their baby’s skin is hot or sweaty, remove one or more layers of bedclothes or bedding, and think about moving them somewhere that might be a bit cooler.”

Use light bedding and dress your baby appropriately

Cotton or muslin bedding are lighter and help to absorb moisture, which will help keep your baby cooler at night.

However, it’s important to reduce layers, for example, putting your baby in a vest without a sleepsuit. If it’s really hot, just a nappy with no bedding is fine, according to the Lullaby Trust. However, it’s important to check on your baby as they may get too cold as the temperature drops overnight.

If they use a sleeping bag, check the tog isn’t too high. Togs usually range from 0.5 to 3.5 and the lower the better in hot weather, but you may want to go without a sleeping bag.

Don’t close the bedroom door

Shutting the door to your baby’s bedroom may stop noises from waking them up, but the lack of air flow can make a room much hotter. Keeping the door open - along with windows - helps the air circulate.

Make sure the cot isn’t in direct sunlight

It’s difficult in a bright room, but make sure your baby’s cot isn’t in direct sunlight as they will likely overheat. Move the cot or moses basket into a darker, shadier corner, or close the curtains or blinds during the day. However, make sure the windows and doors are open to make sure the room doesn’t heat up.

Keep a thermometer in their room

If you’re unsure about how warm your baby’s room is, it’s helpful to keep a thermometer in there so you can quickly check the temperature. There are plenty of options online, including thermometers which double up as night lights.

Use an electric fan

You could also try using an electric fan in the room your baby sleeps in, but don’t point it directly at your baby. If you keep the door and window closed, using a fan may actually make the room hotter, so keep the door and window open.

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Further reading

1. Bach et al: Hyperthermia and heat stress as risk factors for Sudden Infant Death Syndrome: A Narrative Review.