White Noise and Infant Sleep: What Does the Research Actually Show?

By Birth & Baby University · Last updated: October 2026 · 7 min read

White noise is one of the most common tools parents reach for in the newborn weeks. Machines, apps and white noise “sound soothers” are widely sold with claims that they help babies fall asleep and stay asleep. Postpartum doulas are asked whether they work and whether they are safe. The evidence is smaller than the market for the products, and it includes one clear safety concern about volume. This article reviews what systematic reviews, a meta-analysis, a trial in newborns and a measurement study of infant sleep machines show, and where the evidence is weak enough that honest advice has to include “we do not know.”

Key takeaways

Quick answer: the quality of evidence that continuous noise improves sleep is very low according to a systematic review that mostly covered adults, and a small recent meta-analysis found mixed effects in infants and young children. Infant sleep machines can produce sound levels that may be damaging to hearing. If a family uses one, a low volume and a distance from the crib are the main protections.

• A GRADE-rated systematic review of 38 studies concluded that the quality of evidence for continuous noise improving sleep was very low, which “contradicts its widespread use,” and that noise may also negatively affect sleep and hearing.
• A meta-analysis of 12 randomized trials found that in infants and young children white noise prolonged 24-hour total sleep time and reduced awakenings, but did not significantly improve 12-hour nocturnal total sleep time, and the authors note the small number of studies.
• When researchers measured 14 infant sleep machines, all produced more than 50 A-weighted decibels at 30 cm at maximum volume, the recommended noise limit for infants in hospital nurseries, and three exceeded 85 decibels, a level that could risk hearing loss if played for more than 8 hours.
• In a randomized trial of 75 mother-newborn pairs, newborn stress scores decreased after white noise or a recorded lullaby during breastfeeding, but also decreased in the control group.

What the research says

Does it help sleep? Riedy and colleagues’ systematic review (2021) in Sleep Medicine Reviews examined 38 studies of continuous white noise or similar broadband noise and sleep. It found heterogeneity in noise characteristics, sleep measurement methods, adherence and control conditions, with findings ranging from continuous noise improving sleep to disrupting it. Using the GRADE criteria, the quality of evidence that continuous noise improves sleep was very low, and the authors called for research with objective sleep measures and detailed noise descriptions before promoting continuous noise as a sleep aid. That review covered all ages, mostly adults, so it is not a verdict on infants specifically. A newer meta-analysis by Ding and colleagues (2025) pooled 12 randomized trials of 1,301 participants, 356 of them infants and young children aged 0 to 3 years. In that group, white noise was associated with 137.5 more minutes of 24-hour total sleep time (95% confidence interval 67.8 to 207.2) and fewer awakenings over 24 hours and over 12 hours of night, but no significant effect on 12-hour nocturnal total sleep time, 24-hour sleep efficiency or wake after sleep onset. The authors noted the limited number of studies for each outcome in infants. The pooled trials included hospital and intensive care settings, and the abstract does not say how many of the infant trials were done with healthy babies at home, so the findings cannot be assumed to apply there. Taken together, these papers say the evidence is thin and inconsistent, not that white noise does nothing.

Does it help calm newborns? Karakuş Selçuk and colleagues’ 2025 randomized trial in a Turkish hospital assigned 75 mother-newborn pairs to white noise, a recorded lullaby or a control group (25 each) for about 15 minutes during breastfeeding. Newborn stress scores fell significantly after the intervention in both noise groups, but a significant difference was also seen in the control group, and mothers’ comfort and LATCH scores differed between groups. The authors concluded both sounds reduced newborn stress and increased mothers’ comfort. With groups of 25, short exposure, scores reported by researchers and a control group that also improved, this is early, small-scale evidence about a calmer feed, not about longer sleep.

The safety concern: volume. Hugh and colleagues’ 2014 study in Pediatrics measured maximum sound levels of 14 infant sleep machines at 30, 100 and 200 cm, correcting for a 6-month-old’s ear canal. All exceeded 50 A-weighted decibels at 30 cm, the current recommended noise limit for infants in hospital nurseries, and three exceeded 85 decibels, which, if played for over 8 hours, exceeds occupational limits for adult noise exposure and risks noise-induced hearing loss. The authors concluded that sleep machines are capable of producing levels that may damage hearing and auditory development, and they proposed recommendations for safer operation. This is a laboratory measurement of devices at maximum volume, not a study of harm in babies, and it does not show what typical use does.

What this means for doulas

• Be honest about the evidence. “Some babies seem calmer with it, trial evidence is limited, and the volume matters” is accurate. Avoid promising longer sleep.
• Prioritize volume and distance. The measurement study shows that devices at maximum can be loud at close range. A conservative approach is to keep any device at a low volume and across the room, not in or on the crib. The study does not set a “safe” level for babies at home, so say so.
• Keep it off the sleep surface. Anything placed in the sleep space beyond a fitted sheet, including a sound device or a toy with a speaker, conflicts with the AAP’s advice to keep the sleep space bare. See Safe Sleep Recommendations: What Every Postpartum Doula Must Know.
• Use as a tool, not a dependency. No source reviewed here tested whether babies become reliant on white noise, so do not claim either that they do or that they do not.
• Do not rely on sound for medical concerns. A baby who is difficult to settle despite quiet, comfort and feeding may be ill. Use the red flags in Recognizing When a Newborn Needs Medical Evaluation: Essential Red Flags for Postpartum Doulas.

Putting the evidence into practice

1. Ask what the family already uses. A device, a phone app, a fan or a vacuum. Check the volume and where it sits.
2. Set a simple rule: lowest effective volume, across the room, ideally switched off or on a timer when not needed.
3. Compare with other calming tools. Holding, swaddling, feeding and rocking are discussed in Infant Crying Patterns: What Research Tells Us About the First Three Months and Swaddling and Infant Sleep: Benefits, Risks, and When to Stop.
4. Watch for effects. If the baby seems more distressed, wakes more or has a hearing concern, stop the device and tell the pediatric provider.
5. Revisit later. Needs change as babies grow, and families can reassess whether the device still helps.

Limits and uncertainty

Most of the sleep evidence is from adults or from hospital settings, the infant meta-analysis rests on a handful of trials with a wide range of results, and the newborn trial is small and has a control group that also improved. The sleep machine study is a measurement study of products on the market in the early 2010s, tested at maximum volume. No research was found on long-term effects of nightly white noise exposure in healthy babies, on hearing outcomes in babies who use it, or on whether it affects development. This article draws on the abstracts only. Some products, including apps and plush toys with sound, may behave differently from the devices tested, and an article summarizing “how much is too much” that was located had no accessible abstract.

The bottom line

White noise may help some babies settle, but the evidence that it improves sleep is weak and inconsistent, and the one clear safety finding is that devices can be loud enough to risk hearing if used at high volume. Families who use it should keep it low, across the room and off the crib. A doula can provide honest framing, check the setup and keep the focus on safe sleep and the baby’s cues.

Birth & Baby University’s For Doulas page sets out its postpartum doula training, recertification and mentorship for doulas who support families with newborn settling and sleep. Confirm that any program meets your certifier’s, employer’s or state’s requirements before you enroll.

This article is for professional education. It is not medical, legal or tax advice. Check the standards of your certifying organization and the rules where you work. For concerns about a baby’s health, contact a pediatric provider or emergency services.

Sources and further reading

• Riedy SM, et al. Noise as a sleep aid: a systematic review. Sleep Medicine Reviews (2021). Read the source
• Ding Y, et al. Impact of white noise on sleep quality across age groups and in critically ill/non-critically ill patients: a systematic review and meta-analysis of randomized controlled trials. Sleep Medicine (2025). Read the source
• Karakuş Selçuk A, et al. The effect of white noise and recorded lullaby during breastfeeding on newborn stress, mother’s breastfeeding success, and comfort: a randomized controlled trial. Journal of Pediatric Nursing (2025). Read the source
• Hugh SC, et al. Infant sleep machines and hazardous sound pressure levels. Pediatrics (2014). Read the source

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