Is co-sleeping (sharing a bed with an infant or young child) beneficial or harmful for a child's development, particularly in terms of sudden infant death syndrome (SIDS) risk?

Co-Sleeping Is Harmful for Infant Safety and Should Be Avoided

Bed-sharing (co-sleeping) significantly increases the risk of sudden infant death syndrome (SIDS) and other sleep-related deaths, and should not be practiced. Instead, room-sharing without bed-sharing—where the infant sleeps on a separate surface in the parents' bedroom—reduces SIDS risk by up to 50% while maintaining parental proximity. 1, 2

The Recommended Safe Sleep Arrangement

Room-sharing without bed-sharing is the evidence-based standard. 1, 2, 3

• Place the infant's crib, portable crib, play yard, or bassinet directly in the parents' bedroom, close to the parents' bed 1, 2
• Maintain this arrangement ideally for the first year of life, but at minimum for the first 6 months when SIDS rates are highest 2, 4
• This configuration allows parents to hear, see, and respond to infant distress while eliminating suffocation, strangulation, and entrapment hazards present in adult beds 1, 4

Why Bed-Sharing Is Dangerous

The American Academy of Pediatrics states unequivocally that epidemiologic studies have not demonstrated any bed-sharing situations that are protective against SIDS or suffocation 1. The evidence shows bed-sharing increases SIDS risk (odds ratio 2.88) 4, and this risk becomes catastrophically high in certain circumstances 4:

Absolute Contraindications to Bed-Sharing (Never Acceptable)

Parents must avoid bed-sharing in these situations at all times 1, 3:

1. Infants younger than 3 months of age (regardless of any other factors, even if parents are non-smokers) 1, 2
2. With any current smoker (even if they don't smoke in bed) or if the mother smoked during pregnancy 1, 2
3. With someone who is excessively tired 1, 2
4. With someone using medications (antidepressants, pain medications) or substances (alcohol, illicit drugs) that impair alertness or arousal 1, 2
5. With anyone who is not a parent, including other children or siblings 1, 3
6. With multiple persons in the bed 1
7. On soft surfaces such as waterbeds, old mattresses, sofas, couches, or armchairs (sofas carry extraordinarily high risk with odds ratios of 5.1-66.9) 1, 2
8. On surfaces with soft bedding, including pillows, heavy blankets, quilts, and comforters 1

Why These Restrictions Matter

Adult beds contain inherent mechanical hazards—soft bedding, pillows, structural gaps—that create suffocation, strangulation, and entrapment risks 4. Bed-sharing also increases exposure to overheating, rebreathing of exhaled air, airway obstruction, and head covering, all established SIDS risk factors 4. Furthermore, not all risks associated with bed-sharing, such as parental fatigue, can be controlled 1.

The Evidence Supporting Room-Sharing

Room-sharing without bed-sharing provides multiple protective mechanisms 4:

• Enhanced parental monitoring: Parents can immediately detect and respond to changes in breathing patterns, choking, or physiologic compromise 4
• Facilitation of breastfeeding: Nighttime feeding becomes more convenient and sustainable, and breastfeeding itself independently reduces SIDS risk 1, 2, 4
• Prevention of mechanical hazards: Eliminates the suffocation risks inherent to adult beds while maintaining proximity 4
• Improved infant arousal patterns: Close proximity may enhance infant arousability without the dangers of bed-sharing 4

Practical Implementation

Infants may be brought into the parental bed temporarily for feeding or comforting, but must be returned to their own crib or bassinet when the parent is ready to return to sleep 1, 3. This allows responsive caregiving without sustained exposure to bed-sharing hazards.

Additional Safe Sleep Essentials

To further reduce SIDS risk 1, 2, 3:

• Remove all soft objects and loose bedding from the crib (pillows, quilts, comforters, sheepskins, pillow-like toys) 1, 3
• Keep the sleep area free of dangling cords, electric wires, and window-covering cords that present strangulation risk 3
• Avoid devices marketed to make bed-sharing "safe" (in-bed co-sleepers)—these are not recommended 1
• For twins and higher-order multiples, provide separate sleep areas and avoid co-bedding 1, 3

Common Pitfalls to Avoid

Despite cultural practices in many societies where co-sleeping is traditional 5, the evidence unequivocally supports room-sharing without bed-sharing as the safest arrangement 2. Healthcare providers must deliver this message clearly, even when it contradicts cultural norms or parental preferences 6.

The critical period is the first 6 months, when SIDS rates peak 2, 4. In one forensic study, 92.2% of SIDS deaths had at least one sleep-related risk factor present, with 65.7% not in a crib, 61.8% prone, and 47.1% co-sleeping 7. Only 7.8% of SIDS victims had slept alone, in a crib, on their back—the recommended configuration 7.

The recommendation is clear: room-sharing without bed-sharing is the only evidence-based safe sleep arrangement that balances infant safety with parental proximity and responsive caregiving. 1, 2, 4