Room temperature and the amount of clothing and bedding used are associated with increased risk of SUDI. Babies who sleep on their tummy are at an even greater risk of overheating, so in addition to always placing baby to sleep on their back, be vigilant to temperature and bedding when baby begins to roll.

The ideal temperature for a baby’s room is between 16-20 degrees. It’s important to consider baby’s clothes and blankets and the air flow within the room when it comes to managing temperature. Clothes and bedding should be lightweight – 100% cotton is best as it is more breathable.

‘What if baby has a fever?’ – You don’t need to put extra blankets on your baby when they are ill, even in winter. If your baby is feverish, it is especially important not to bundle him/her up in too many bedclothes. Bringing an unwell baby into your bed puts them at an increased risk of overheating. Although baby may need comforting, avoid situations where they are likely to become even more warm.

Babies and toddlers under 12 months old are not able to regulate their temperature very well. This function develops as they grow. Until then you have to make choices to ensure your child is in a room of the ideal temperature and is dressed with the number and types of layers appropriate for the temperature of the environment that they are in. 

To check the temperature of your baby, check the back of his/her neck with the back of your hand. It should feel warm. If he/she feels hot or his/her skin is damp from sweating, remove some of the bedding. A normal temperature in babies and children is about 36.4C (NHS)

It is important to ensure that you only use light blankets in your baby’s cot:  Use one or more layers of light blankets, depending on the room temperature. Remember that one blanket doubled over counts as two blankets.

Remember that a blanket folded over once counts as 2 blankets, and a blanket folded over twice counts as 4 layers of blanket etc.

If you choose to use a baby sleeping bag, choose one that doesn’t have a hood. Ensure that you choose the right size for your baby, and tog-rating for the season. Different brands will have different tog values, so it is important to read the packaging carefully before you use the sleeping bag.

Do not place a hat on a baby’s head when putting them down to sleep, unless it has specifically been recommended for medical reasons.

For a useful guide on what clothing and bedding to use, you can purchase our  Room thermometer 

Temperature and the use of clothing and bedding are closely linked but the actual role of temperature on SUDI risk is not quite so straightforward. Many previous studies have shown the evidence around overheating to be linked with many other variable factors. There may be an association with SUDI due to head covering by loose bedding, rebreathing of air around the nose and mouth or suffocation by baby lying with their face into a soft surface from layers of bedding, pillows etc.

Another way to think about this topic is to consider the temperature of the air that baby breathes.

It may be that it is the airflow that is more critical, not the actual temperature. Some research shows that SUDI occurs more in rooms where heating was used compared to no heating. Where there is good airflow and ventilation, there may be a decreased risk of SUDI.


Evidence For Our Temperature Safe Sleep Message

Overheating can increase the risks of cot death by as much as 2,5 times.
Heating set to an inappropriately high temperature being used in the room baby sleeps has been shown to increase the risk of SUDI by up to 4.5 times greater

In one study head covering with bedding happened in 25% cases of SUDI but in only 3% of control cases.

It is important to note that the consensus view in the UK is that a temperature of 16-20C offers a comfortable and safe environment for a baby to sleep, although is not strongly evidence-based.

Parents do find guidance on this topic helpful as an individuals own level of comfort in different room temperatures varies so greatly.


Link to research articles