Safe Sleep for Babies and Toddlers: A Complete Guide for New Parents

Understanding the Risk

Sudden Infant Death Syndrome (SIDS), sometimes called cot death, is the sudden and unexplained death of an apparently healthy baby, usually during sleep. Around 200 babies die from SIDS in the UK each year. The causes are not fully understood, but research has identified a set of factors that increase risk and a set of evidence-based practices that substantially reduce it.

Following the safe sleep guidance does not eliminate risk completely, but it does significantly reduce it. Parents who follow the guidance consistently give their baby the best possible protection and can sleep themselves with the knowledge that they have done everything in their power. This guide covers what the evidence actually recommends.

The Fundamental Safe Sleep Rules

The single most important safe sleep recommendation is to place babies on their back to sleep for every sleep, including daytime naps. Before this was widely adopted following research in the 1990s, SIDS rates in the UK were around three times higher than they are today. Side or front sleeping significantly increases SIDS risk. Once a baby can roll to their front independently, you do not need to turn them back, but always place them on their back initially.

The second key recommendation is room-sharing without bed-sharing. Keep your baby in the same room as you for all sleeps, day and night, for at least the first six months. This is strongly associated with reduced SIDS risk. However, sharing a sleep surface (co-sleeping) significantly increases the risk, particularly if either parent smokes, has consumed alcohol or sedating medication, or is very tired.

The sleep environment should be a clear, firm, flat surface without pillows, duvets, bumpers, rolled blankets, or soft toys. Cot bumpers are not recommended even when fabric covered, as they can impede airflow. Use a firm, flat, waterproof mattress that fits the cot properly without gaps. Loose bedding increases risk; a correctly sized sleep bag is a safer alternative to blankets for babies who move during sleep.

Temperature

Overheating is associated with increased SIDS risk. The ideal room temperature for a sleeping baby is between 16 and 20 degrees Celsius. A baby who is too warm will feel sweaty and hot on the back of the neck or chest. Remove a layer of clothing or bedding if this is the case.

Do not place a cot next to a radiator, in direct sunlight, or near a window where sunlight will fall. Avoid hats indoors during sleep. A room thermometer is a useful and inexpensive tool for monitoring sleep environment temperature.

Smoking and SIDS

Smoking is one of the strongest avoidable risk factors for SIDS. Babies whose mothers smoked during pregnancy have a significantly increased risk. Babies who are exposed to second-hand smoke after birth also have elevated risk. Do not allow anyone to smoke inside the home or in the car. The risk associated with smoking is present even if parents smoke and then go outside; particles remain on clothing, hair, and furniture.

Co-sleeping with a baby when either parent is a smoker is particularly strongly associated with SIDS risk and is strongly contraindicated by all UK health bodies, including in situations where the parent has not smoked that day.

Feeding and SIDS

Breastfeeding is associated with reduced SIDS risk. If you are able to breastfeed, even for a short period, this provides a degree of protection. If breastfeeding is not possible or sustainable for your family, formula feeding is safe and the safe sleep guidance applies equally regardless of feeding method.

A dummy used at sleep time is associated with reduced SIDS risk, though the mechanism is not fully understood. If you choose to use a dummy, introduce it once breastfeeding is established (around three to four weeks). Never force it if the baby does not want it and do not reinsert it once the baby is asleep. Do not use sweetened dummies or attach them to strings that could cause strangulation.

When to Be Concerned

If your baby is unresponsive, has stopped breathing, or if you cannot wake them, call 999 immediately. Begin infant CPR if you know how and if the baby is not breathing. If you are not sure how to perform infant CPR, St John Ambulance and the Red Cross provide free training resources and short instructional videos online.

Signs that warrant calling 111 or seeking medical attention include a baby who seems unusually difficult to rouse, who has an unusual high-pitched cry, who has a fever, who has a rash, or who appears to be breathing with unusual effort. Trust your instincts as a parent. If something does not seem right, seek assessment rather than waiting.