Pacifiers and SIDS: the protective effect explained

The AAP recommends offering a pacifier at the start of every sleep during the first year of life.¹ This recommendation surprises many parents — pacifiers are often thought of as a habit to avoid, not a safety tool. But the association between pacifier use at sleep time and reduced SIDS risk is one of the more consistent findings in the safe sleep evidence base.

What the evidence shows

Multiple epidemiological studies have found that infants who use a pacifier at sleep time have a lower rate of SIDS death than those who don't. The AAP 2022 sleep guidelines describe this as a "consistent" association across studies, strong enough to justify an active recommendation to offer a pacifier.¹

The magnitude of the apparent effect is substantial — some studies show a reduction of 50–90% in SIDS risk among pacifier users, though the absolute SIDS rate is already low and these are observational findings, not clinical trials.¹ The NHS acknowledges the association, noting that some studies suggest dummy use may help.²

Why it might work: the leading theories

The mechanism behind the pacifier–SIDS association is not fully established. Three hypotheses have reasonable support:

Arousal threshold. SIDS involves a failure to rouse when oxygen levels drop. Infants who use a pacifier during sleep may have lower arousal thresholds — they wake more easily in response to physiological stress. Sucking on a pacifier appears to keep infants in a lighter, more responsive sleep state.¹

Airway patency. Sucking creates muscle tone in the upper airway and positions the tongue forward. A pacifier may keep the airway mechanically more open than it would otherwise be in a sleeping infant, who has low muscle tone throughout.

Sleep architecture. Pacifier use is associated with higher proportions of active (lighter) sleep and fewer episodes of very deep quiet sleep — the sleep state in which arousal failure is most likely to occur.

None of these mechanisms have been definitively proved, and they are not mutually exclusive. The AAP recommendation rests on the epidemiological association, which is consistent even if the mechanism remains uncertain.¹

When to introduce

The delay for breastfeeding families exists because of concerns about nipple confusion — that early pacifier introduction might interfere with breastfeeding technique or supply. The evidence on this is mixed, but as a precaution the AAP recommends waiting until breastfeeding is established before introducing a pacifier.¹

If your baby refuses the pacifier, that's fine. The recommendation is to offer, not to force. Do not try to keep the pacifier in place if the baby doesn't want it. And if the pacifier falls out after your baby falls asleep, there is no need to replace it.¹

What not to do

Do not dip the pacifier in anything sweet. Coating a pacifier in sugar, honey, or other sweeteners to encourage acceptance creates dental decay risk and is strongly contraindicated. Honey specifically must not be given to infants under 12 months due to the risk of infant botulism.¹²

Do not attach the pacifier to the baby or to the cot. Cords, clips, ribbons, and chains attached to pacifiers are strangulation hazards. The pacifier goes in, falls out, and that's the end of it.

Do not use a damaged or worn pacifier. A deteriorating silicone or rubber teat can break apart, creating a choking hazard. Inspect pacifiers regularly and replace them at the first sign of cracking, stickiness, or teat distortion.

How long to use a pacifier

The SIDS-protective benefit of pacifiers applies specifically during the peak SIDS risk window: birth to 12 months, with risk concentrated in the 1–4 month age range.¹ After 6 months, SIDS risk falls substantially. After 12 months, it is rare.

This means the safety argument for offering a pacifier at sleep time applies most strongly in the first 6–12 months.

The question of when to stop entirely is separate from the safety question. Prolonged pacifier use — typically defined as beyond 2–3 years — is associated with some dental effects (open bite, changes to palate shape) and with delayed speech clarity in some children.² Most professional bodies, including the NHS, suggest weaning pacifier use by around age 2–3 for dental and speech reasons, and earlier if possible.²

Between 12 months and the age you choose to wean, pacifier use during sleep is not harmful. Many families find their child naturally loses interest between 1 and 2 years.

A note for breastfeeding families

Breastfeeding itself is independently associated with reduced SIDS risk — the AAP cites approximately 50% risk reduction with consistent breastfeeding.¹ If your baby breastfeeds to sleep and refuses a pacifier, the breastfeeding association alone is meaningful. A pacifier does not need to be forced on a baby who won't take one.

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Also in this cluster: Back to sleep · Swaddling: how to do it safely and when to stop

Sources

1. American Academy of Pediatrics. "Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment." Pediatrics 150(1), 2022. https://publications.aap.org/pediatrics/article/150/1/e2022057990/188304/Sleep-Related-Infant-Deaths-Updated-2022-Recommendations
2. NHS. "Should I give my baby a dummy?" NHS, 2024. https://www.nhs.uk/conditions/baby/caring-for-a-newborn/dummies/