Safer sleep guidance around the world agrees on the core: babies sleep on their backs, on a firm flat surface, in their own clear sleep space, in the same room as an adult for the early months. Countries differ on bed sharing, and that difference is real rather than a translation problem, so this page describes both positions and points you to the advice where you live. This is health information for learning and it is not medical advice about your baby. Anything about your own baby's sleep, breathing or health belongs with a health visitor, paediatrician or emergency service.
What the guidance is for
Sudden infant death syndrome, or SIDS, is the sudden unexplained death of an apparently well baby. CDC groups it with other sudden unexpected infant deaths, including deaths from accidental suffocation and strangulation in bed.
Nothing removes the risk entirely, and no parent causes it by being tired. Safer sleep guidance exists because a small number of changes to where and how a baby sleeps are linked with lower risk.
NHS guidance says the risk is highest in the first six months, that it can affect babies up to a year old, and that it can happen at any sleep, day or night.
Where guidance agrees
On the back, for every sleep, naps included. NHS and AAP guidance both say back sleeping, and both say to move a baby onto their back if they roll before they can roll both ways on their own.
On a firm, flat surface, with a fitted sheet and nothing else. No pillows, duvets, cot bumpers, loose blankets, soft toys, pods or nests.
In the same room as an adult for the first six months, in the baby's own cot, crib or Moses basket. Never on a sofa or armchair with a baby, which both bodies name as one of the most dangerous places to fall asleep together.
Not too hot. NHS guidance suggests a room around 16C to 20C, checking the baby's chest or the back of the neck rather than hands and feet, and taking hats and extra layers off indoors.
No smoking in pregnancy or around the baby, and nobody smoking in the same room. Where a baby falls asleep in a car seat, pram, swing or sling, both bodies advise moving them to a flat surface when you can.
Premature babies are a special case. NHS guidance says to follow safer sleep advice for a year from the original due date rather than the birth date.
Where guidance differs, and how to handle it
Bed sharing is the split. AAP does not recommend bed sharing at any point in the first year, and advises room sharing without it.
NHS guidance also says the safest place is a separate cot or Moses basket, and then gives advice on sharing a bed more safely, because many families do it whether or not it is recommended. That advice includes a firm flat mattress, the baby on their back, pillows and blankets kept away from the baby, no swaddling, no other children or pets in the bed, and never leaving the baby alone in an adult bed.
Both agree on when bed sharing is most dangerous. NHS guidance says never share a bed if you or a partner smoke, have drunk alcohol, or have taken drugs or medicine that makes you drowsy, and not if the baby was born before 37 weeks or weighed under 2.5kg at birth.
Follow the guidance published where you live, and tell your midwife or health visitor honestly how your baby actually sleeps. A plan built on what really happens at four in the morning is safer than one built on what should happen.
Other things linked with lower risk
NHS guidance names breastfeeding, offering a dummy for sleep, and keeping a baby up to date with routine vaccinations as things associated with lower SIDS risk. Your baby's first checks and vaccinations covers what is usually offered and when.
None of these are a substitute for the sleep position and the sleep space, which are the parts with the strongest evidence behind them.
When exhaustion is the real problem
Most unplanned bed sharing happens because a parent falls asleep feeding, not because anyone decided to. Knowing that in advance is why guidance is worth reading before the hard night rather than during it.
If you are so tired that you fall asleep wherever you sit, that is a reason to ask for help. See sleep and exhaustion after birth, and newborn crying for the nights that will not end.
When to see a doctor
Seek urgent care for any sign in the box below, at any hour. Sleep advice never overrides a baby who looks unwell.
Ask a health visitor or doctor about sleep if your baby will only sleep upright, if breathing during sleep worries you, or if your baby was born early or has a health condition and you are unsure which advice applies. See your newborn in the first two weeks for what is usual, and newborn warning signs for what is not.
Seek care now: Contact your local emergency services or go to your nearest emergency department if a baby under three months old has a temperature of 38C or higher, is breathing fast, working hard to breathe or grunting, has blue, grey, pale or mottled skin, is floppy, is difficult to wake, is refusing feeds, has far fewer wet nappies or none in the past 12 hours, has a bulging or sunken soft spot on the head, has a rash that does not fade when you press it, or has a fit. Femio cannot assess a baby.
Frequently asked questions
What if my baby rolls onto their front?
Guidance is to always place a baby on their back, and to turn them back until they can roll both ways by themselves. Keep the cot clear of anything they could roll into.
Is bed sharing banned?
Guidance differs. AAP advises against bed sharing; NHS advice names a separate cot as safest and then explains how to share a bed more safely. Both agree it is dangerous after alcohol, drugs or drowsy medicine, if anyone smokes, and never on a sofa or armchair.
Are sleep positioners, pods and nests safe?
Guidance advises against anything in the cot that could cover a baby's face, and against products not designed and approved for infant sleep.
Can a baby choke on their back?
Guidance is clear that back sleeping is advised for all babies, including babies who bring up milk. Ask a paediatrician if your baby has a condition that makes you unsure.