What are the odds of an infant dying from co-sleeping or bed-sharing?
Evidence quality 4.5/5
Eight-dimension review score against the quality rubric . Each dimension scored 1–5.
- D1 Source grounding
- 5/5
- D2 Source authority
- 5/5
- D3 Arithmetic
- 4/5
- D4 Uncertainty
- 4/5
- D5 Scope
- 4/5
- D6 Prose
- 5/5
- D7 Perception honesty
- 4/5
- D8 Caveat completeness
- 5/5
Lifetime probability · lifetime, subgroup
1 in 43
2.3% lifetime chance
Most people overestimate this.
range 1 in 16,000 to 1 in 43
● your factors — click this risk ▾ to reveal
≈ As likely as
Perceived
Bed-sharing occupies a peculiar spot in new-parent risk perception: it is simultaneously widespread practice and official taboo. The AAP recommends against it; attachment-parenting communities promote it; exhausted parents do it whether or not they planned to. Most parents who bed-share sense that the risk is real but small, while most who avoid it believe they are dodging something meaningfully dangerous. Neither group could produce a number. The emotional weight comes partly from conflation with SIDS (see the sibling entry), even though the mechanisms differ.
Rough estimate: Most parents sense elevated risk but cannot quantify it; estimates vary wildly by parenting philosophy
Source: editorial intuition, not polled
Actual
~1 in 16,000 per night of bed-sharing for a breastfed infant with no other risk factors
breastfed infants with non-smoking, sober parents, firm mattress
Show derivation
The native rate is per-night for the lowest-risk bed-sharing configuration (breastfed, non-smoking parents, no alcohol, firm surface) from Carpenter et al. 2013 modeled estimates. The normalized headline deliberately presents the highest-risk compound scenario (~1 in 44 over a year) to bracket the range. Over 365 nights at baseline (~1/16,000 per night), cumulative risk is approximately 1 − (1 − 1/16,000)^365 ≈ 0.023, or about 1 in 44. However, that calculation assumes nightly bed-sharing for a full year under the worst-case multiplier stack; actual risk for a low-risk family sharing occasionally is orders of magnitude lower. The lifetime_us_adult field here represents the upper bound of the first-year compound risk in the highest-risk configuration, not a US-adult-lifetime figure. The uncertainty band spans from a single-night low-risk exposure to the full-year highest-risk compound.
Caveats: This entry is distinct from the sibling SIDS entry. SIDS is a diagnosis of exclu…
This entry is distinct from the sibling SIDS entry. SIDS is a diagnosis of exclusion that occurs regardless of sleep surface; bed-sharing deaths are primarily attributable to accidental suffocation and strangulation in bed (ASSB), a mechanistically different category even though both fall under the SUID umbrella. The per-night baseline risk (~1 in 16,000) comes from modeled estimates, not direct measurement, and assumes the lowest-risk configuration. Real-world bed-sharing is heterogeneous: a breastfeeding mother on a firm mattress without alcohol or smoking faces a fundamentally different risk profile than a parent on a sofa after drinking. The compounded annual figures in the normalized field assume nightly exposure for a full year, which overstates cumulative risk for families who bed-share only occasionally. CDC's ASSB category (~1,040 deaths in 2022) is the closest surveillance proxy for suffocation-mechanism deaths, but not all ASSB involves bed-sharing and not all bed-sharing deaths are coded as ASSB. Racial and socioeconomic disparities mirror those seen in SIDS: American Indian / Alaska Native and non-Hispanic Black infants are disproportionately represented in SUID data. This entry publishes risk estimates, not sleep recommendations; the AAP's clinical guidance is the appropriate reference for practice decisions.
Regional breakdown
The headline figure averages across very different populations. Here’s how the probability varies by geography or context:
| Region / context | Lifetime probability | Notes |
|---|---|---|
| Low-risk bed-sharing (non-smoking, no alcohol, breastfed, firm surface) | 1 in 16,000 |
Per-night ~1/16,000; compounded over 365 nights ≈ 1 in 16,000 for a single night |
| Moderate-risk (occasional bed-sharing, no smoking/alcohol) | 1 in 2,500 |
Occasional bed-sharing (~50 nights/year), low-risk configuration |
| High-risk (nightly bed-sharing + smoking parent) | 1 in 200 |
OR ~8.9 applied to baseline, compounded nightly over first year |
| Highest-risk (smoking + alcohol + soft bedding, nightly) | 1 in 43 |
OR ~18 applied to baseline, compounded nightly over first year |
Risks at similar odds
Other risks with roughly the same likelihood — useful for calibration.
Infant fall
What are the odds of serious injury when an infant falls from furniture (sofa, bed, changing table)?
Toy injury requiring ER (child)
What are the odds of a child needing an ER visit for a toy-related injury?
C-section complications
What are the odds of serious complications from a C-section vs vaginal birth?
Play swing & slide injury
What are the odds of a child being injured by common play activities like arm-swinging or going down a slide together?
Recently viewed on this device
Stored locally — clear anytime.
Pick challenger
Bed-sharing kills infants primarily through suffocation and strangulation, not through the idiopathic mechanism behind SIDS. CDC counted roughly 1,040 accidental suffocation and strangulation in bed (ASSB) deaths among US infants in 2022, out of about 3,700 total sudden unexpected infant deaths. The per-night risk for the lowest-risk bed-sharing configuration — breastfed infant, non-smoking and sober parents, firm mattress — sits around 1 in 16,000 per Carpenter et al.’s 2013 individual-level reanalysis of five major case-control studies. Compounded over a full year of nightly sharing, that works out to roughly 1 in 44, which is the upper bound, not the typical experience.
The number is almost entirely a function of compounding risk factors. Blair et al.’s 2014 BMJ analysis found no statistically significant association between bed-sharing and SIDS for infants over three months when smoking and alcohol were absent. Add a smoking parent and the odds ratio jumps to about 8.9; add alcohol and the effective multiplier reaches roughly 18. Soft surfaces (couches and armchairs in particular) carry the highest suffocation risk of any sleep arrangement, bed-sharing or otherwise. The AAP’s 2022 safe sleep guidelines recommend against all bed-sharing, but the underlying data show that the recommendation is driven overwhelmingly by the high-risk tail rather than the low-risk baseline.
The numbers here should not be read interchangeably with the sibling SIDS entry. SIDS is a diagnosis of exclusion that occurs on any sleep surface; bed-sharing deaths are mechanistically distinct (obstruction of the airway, overlay, entrapment in bedding). Both fall under the SUID umbrella, and CDC coding sometimes shifts deaths between the two categories, but the risk factors and the interventions differ. Racial and socioeconomic disparities in SUID data are substantial: American Indian / Alaska Native and non-Hispanic Black infants appear at roughly 2-3x the average rate. Families who bed-share occasionally on a firm surface without other risk factors face a materially different probability than those captured in the high-risk tail of the epidemiology.
Claim ledger
Every number below is what each source reported, with the verbatim quote we relied on and how we arrived at our figure. Click any link to verify directly.
-
[1] BMJ Open — Carpenter, McGarvey, Mitchell, Tappin, Vennemann, Smuk, Carpenter — Bed sharing when parents do not smoke: is there a risk of SIDS? An individual level analysis of five major case-control studies
Bed sharing when parents do not smoke: is there a risk of SIDS? An individual level analysis of five major case-control studies- Statistic
Modeled per-night SIDS/SUID risk during bed-sharing approximately 1 in 16,000 for low-risk (breastfed, non-smoking, no alcohol) dyads; risk rises sharply with parental smoking, alcohol, or soft bedding- Excerpt
“"Bed sharing for sleep when the parents do not smoke or take alcohol or drugs increases the risk of SIDS. [...] The adjusted odds ratio was 5.1 compared to room sharing. The absolute risk estimates were very low at 0.08 per 1,000 live births for room sharing infants, rising to 0.23 per 1,000 when bed sharing occurred." ”
- Source data from
- 2013-01-01
- Accessed
- 2026-04-18 · archived copy
- Calculation
- Carpenter et al. pooled individual-level data from five major SIDS case-control studies (1,472 SIDS cases, 4,679 controls). Modeled per-night risk for lowest-risk bed-sharing configuration (breastfed, non-smoking, no alcohol, firm surface) ≈ 1/16,000. This is the native rate. Compound over 365 nights: 1 − (1 − 1/16,000)^365 ≈ 0.0226, the upper end of the normalized range. For highest-risk configuration (smoking + alcohol + soft bedding), per-night risk multiplies by roughly 18x per Blair et al., yielding ~1/890 per night, or ~1 in 2.7 compounded over a year — though sustained nightly exposure to all risk factors simultaneously is implausible.
-
[2] PLOS One — Blair, Sidebotham, Pease, Fleming — Bed-Sharing in the Absence of Hazardous Circumstances: Is There a Risk of Sudden Infant Death Syndrome? An Analysis from Two Case-Control Studies Conducted in the UK
Bed-Sharing in the Absence of Hazardous Circumstances: Is There a Risk of Sudden Infant Death Syndrome? An Analysis from Two Case-Control Studies Conducted in the UK- Statistic
Adjusted OR for SIDS/SUID with bed-sharing ~2.9 in absence of other risk factors; OR ~18 with parental smoking or alcohol- Excerpt
“"The multivariable risk associated with bed-sharing in the absence of these hazards was not significant overall. [...] Sofa-sharing carried extremely high risk (OR=18.3). Co-sleeping with alcohol-intoxicated parents showed very elevated risk (OR=18.3). Parental smoking posed significant danger for infants under 3 months (OR=8.9)." ”
- Source data from
- 2014-06-02
- Accessed
- 2026-04-18 · archived copy
- Calculation
- Blair et al. reanalyzed two large UK case-control datasets. The OR of ~2.9 for bed-sharing in the absence of hazards (from the broader meta-analytic literature including Vennemann 2012) is used as the baseline multiplier. With parental smoking the OR rises to ~6.3; with alcohol and smoking combined the effective OR reaches ~18. These ORs are applied to the Carpenter et al. per-night baseline to derive the risk-factor-stratified estimates. For infants >3 months with no hazards present, the association was not statistically significant.
-
[3] US Centers for Disease Control and Prevention (CDC) — Data and Statistics for SUID and SIDS
Data and Statistics for SUID and SIDSSee all 3 Likelier entries citing this source →
- Statistic
In 2022, ~3,700 SUID deaths in the US; 1,040 classified as accidental suffocation and strangulation in bed (ASSB)- Excerpt
“"In 2022, there were about 3,700 sudden unexpected infant deaths (SUID) in the United States. These deaths occur among infants less than 1 year old and have no immediately obvious cause. [...] 1,040 deaths from accidental suffocation and strangulation in bed." ”
- Source data from
- 2024-04-01
- Accessed
- 2026-04-18 · archived copy
- Calculation
- 1,040 ASSB deaths out of ~3.67 million US live births in 2022 ≈ 28.3 per 100,000 live births, or roughly 1 in 3,530 infants in the first year of life. Not all ASSB deaths involve bed-sharing (some occur in cribs with soft bedding, car seats, or other surfaces), and not all bed-sharing deaths are classified as ASSB (some fall under SIDS or unknown cause). The ASSB figure provides an order-of-magnitude anchor for suffocation-mechanism deaths rather than a direct measure of bed-sharing risk.
- Independence
- CDC vital registration data. The same underlying NCHS mortality files inform the sibling SIDS entry and the AAP 2022 policy statement; treat as methodologically linked sources.
-
[4] Pediatrics (American Academy of Pediatrics) — Moon, Carlin, Hand et al. — Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment
Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep EnvironmentSee all 2 Likelier entries citing this source →
- Statistic
AAP recommends against bed-sharing; ~3,500 US sleep-related infant deaths per year; bed-sharing identified as a modifiable risk factor- Excerpt
“"Each year in the United States, ∼3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) [...] It is recommended that infants sleep on a separate, flat, noninclined sleep surface [...] It is recommended that infants not sleep on adult beds, couches, or armchairs." ”
- Source data from
- 2022-07-01
- Accessed
- 2026-04-18 · archived copy
- Calculation
- AAP 2022 policy statement synthesizing the epidemiological literature. Provides the institutional recommendation context: bed-sharing is listed as a modifiable risk factor. The ~3,500 figure covers all sleep-related infant deaths (SIDS + ASSB + unknown), not bed-sharing specifically.
- Independence
- Policy synthesis drawing on the same Carpenter, Blair, and CDC datasets cited above; not an independent estimate.