Safe Sleep for Your Baby
Safe sleep guidance exists for a clear reason — it works. The UK SIDS rate has fallen by over 80% since the Back to Sleep campaign began in 1991. Understanding why these guidelines matter makes them much easier to follow.
🌿 Open full lesson in WiseMama — free, with quizzes & flashcardsThe Safe Sleep Guidelines
The following guidance is drawn from the Lullaby Trust, the UK's leading SIDS charity, and is aligned with NHS recommendations. Each guideline exists because the evidence shows it reduces the risk of sudden infant death — and taken together, they are remarkably effective.
Back to sleep, every time
Place your baby on their back for every sleep — day and night. This is the single most important safe sleep recommendation. The risk of SIDS is significantly higher when babies sleep on their front or side. Once a baby can roll from back to front independently, you do not need to keep repositioning them — but you should always start them on their back.
Clear, flat, firm sleep surface
Your baby should sleep on a firm, flat, waterproof mattress covered with a fitted sheet. The cot, crib, or moses basket should be free of pillows, duvets, bumpers, positioning wedges, soft toys, and loose bedding. These items pose a suffocation risk even when they seem positioned safely.
In the same room as you — for the first 6 months
The Lullaby Trust and NHS both recommend room-sharing (your baby sleeping in their own sleep space in your room) for the first six months. Research consistently shows this reduces SIDS risk, likely because your breathing and movement provides regulatory signals for your baby's immature nervous system, and because you are more likely to notice if something is wrong.
Temperature
Keep the room at 16–20°C. Overheating is a SIDS risk factor. Your baby should feel warm at their chest or back, but not hot. Check that their head is uncovered during sleep — sleeping bags are safer than blankets for this reason. Remove outdoor clothing before a sleep in a pram or car seat.
Smoke-free environment
Both smoking during pregnancy and exposure to second-hand smoke after birth significantly increase SIDS risk. This applies to the home, car, and any environment where the baby regularly sleeps or spends time.
I read the Lullaby Trust guidelines and thought they were impossible. Then a baby in my NCT group went to hospital with a breathing scare linked to an unsafe sleep environment. I reorganised the whole nursery that day. The guidelines feel inconvenient until you understand what they're protecting against.
SIDS: What We Know
Sudden Infant Death Syndrome (SIDS) — also called cot death — is the sudden, unexplained death of a baby who appeared healthy. It is rare: approximately 200 babies die from SIDS in the UK each year, a rate of around 0.3 per 1,000 live births.
SIDS is most likely caused by an interaction between a vulnerable infant (perhaps one with a subtle brain stem abnormality affecting arousal), a sensitive developmental period (most SIDS deaths occur between 2 and 4 months), and an environmental stressor (a trigger such as prone sleeping position, overheating, or exposure to tobacco smoke). This is the triple risk model.
Risk factors and protective factors
- Risk factors: prone sleeping, maternal smoking (during pregnancy and after), second-hand smoke, soft sleep surfaces, overheating, very young maternal age, prematurity, low birth weight, male sex
- Protective factors: back sleeping, breastfeeding, room-sharing (not bed-sharing), dummy use during sleep (offer after one month if breastfeeding), smoke-free environment, appropriate temperature
Co-Sleeping: The Evidence and Safer Practices
Co-sleeping — sharing a sleep surface with your baby — is officially advised against by the NHS and the Lullaby Trust because it increases SIDS risk, particularly in combination with certain risk factors. This is important information that should be communicated clearly.
At the same time, it is also true that many parents co-sleep, often unplanned — falling asleep while feeding on a sofa or in a bed. Providing guidance on how to make co-sleeping safer, where it does occur, is more useful than guidance that is simply "never do this" and leaves exhausted parents without any framework.
Factors that significantly increase bed-sharing risk (avoid if any apply)
- Either parent smokes (even if not in the bedroom)
- Either parent has consumed alcohol or sedating medication
- Either parent is extremely tired
- Baby was premature (born before 37 weeks) or had a low birth weight
- Baby is under 3 months old
If you do bed-share
Use a firm mattress. Remove pillows and duvets from the area where the baby will be, or use a very light blanket tucked well down. Baby should be on their back, not between parents, and not near the headboard or against a wall. The C-position (lying on your side curled around the baby, with knees drawn up below the baby's feet) prevents rolling toward the baby.
Our baby would only sleep on us for the first six weeks. We nearly fell asleep on the sofa with her because we were so exhausted. We eventually found a bedside crib that meant I could pull her close for comfort without full bed-sharing. That kit exists — find it before you need it.
When Your Baby Will Only Sleep on You
One of the most common scenarios that leads to unplanned, unsafe co-sleeping is a baby who will only sleep while being held. This is biologically completely normal — it is the fourth trimester in action. It does not mean you have created a bad habit, and it will not last forever. But it does mean you need practical strategies for the immediate situation.
- Bedside crib or next-to-me crib — attaches to the side of your bed, allowing you to pull the baby close and transfer them more easily. The baby is on a separate sleep surface while feeling physically close to you.
- Warm the sleep surface before transfer — a briefly placed wheat bag or warm (not hot) water bottle, removed before you lay the baby down, reduces the temperature contrast that often wakes them.
- Keep your hand on their chest for a few minutes after transfer — the warmth and pressure mimics being held and can ease the transition.
- Consider a sling during the day — meeting the baby's need to be held during the day can sometimes reduce its intensity at night.
- Share the load at night — if your partner can take a shift, it protects both of you from the level of exhaustion that leads to falling asleep in an unsafe position.
The NHS recommends waiting until your baby is at least 12 months old before introducing a pillow, and until they are at least one year old before using a duvet. Until then, a well-fitted sleeping bag in the appropriate tog for the room temperature is the safest option. Sleeping bags also prevent blankets from covering the baby's face.
Bouncy chairs, swings, car seats, and pram seats are not recommended as regular sleep surfaces. They allow the baby's head to fall forward, which can obstruct the airway — particularly in very young babies whose neck muscles are not yet strong. If your baby falls asleep in one of these, transfer them to a flat sleep surface as soon as it is safe to do so. Car seats are for travel only, not for extended or unsupervised sleep.
Once a baby can roll from back to front independently — which typically happens around 4–6 months — you no longer need to reposition them during the night. Their ability to roll means they have the muscle strength and motor control to manage their own position. You should, however, continue to place them on their back at the start of every sleep. Ensure the sleep surface remains clear of soft items they could roll into.
Baby monitors are not a substitute for room-sharing. The recommendation to room-share for the first six months is based on evidence that the physical proximity of a parent reduces SIDS risk — a monitor does not replicate this. After six months, if your baby moves to their own room, a monitor is a useful tool but should not be treated as a safety device equivalent to room-sharing.