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Infant & toddler sleep: research and statistics

A sourced reference for parents, journalists, and researchers. Every statistic on this page links to its primary source.

Last updated: June 2026 · Reviewed annually · Cite this page ↓

Understanding infant sleep — what's normal, what isn't, and what the research actually says — requires navigating a field full of contradictory advice, unsourced claims, and genuinely complex science. This page compiles the most relevant statistics and research findings on infant and toddler sleep, parent sleep deprivation, and the professional help landscape across Europe. Each statistic is cited with its source, year, and sample size so you can verify it independently.

Section 1

How long parent sleep deprivation lasts

The most commonly asked question among new parents isn't about their baby's sleep. It's about their own.

This finding is from a large longitudinal study of 4,659 parents in Germany, published in Sleep in 2019 by researchers at the University of Warwick and the German Institute for Economic Research. Sleep satisfaction and duration declined sharply after childbirth, hitting their lowest point at three months postpartum, and did not return to pre-pregnancy levels for either parent within the six-year study window.

6 years
Neither parent's sleep fully recovers for up to 6 years after the birth of a first child.
Richter et al., Sleep, 2019 · n=4,659
7 in 10
Parents lost at least 3 hours of sleep per night on average in the first year — around 133 lost nights by their baby's first birthday.
Snuz survey, n=1,300 UK parents, 2022–23

In the first three months, mothers lost an average of one hour of sleep per night versus before pregnancy. Fathers lost about 15 minutes. Six years later, mothers were still around 25 minutes below baseline; fathers remained 15 minutes below.

The impact on mothers is consistently larger regardless of breastfeeding status. Researchers linked this partly to unequal parental leave: fathers returning to work maintained more regular sleep schedules, while mothers on extended leave carried a greater share of night-time care. Sleep quality also deteriorates — even when total hours were comparable, fragmented postpartum sleep was significantly less restorative.

Sources
  • Richter D, Krämer MD, Tang NKY, Montgomery-Downs HE, Lemola S. "Long-term effects of pregnancy and childbirth on sleep satisfaction and duration of first-time and experienced mothers and fathers." Sleep. 2019;42(4):zsz015. DOI: 10.1093/sleep/zsz015. Sample: n=4,659 German parents (SOEP panel, 2008–2015). [link]
  • Snuz survey, n=1,300 UK parents. 2022–2023. Reported via Cradlewise.
Section 2

How many babies have sleep problems

Sleep difficulties in infancy are the norm, not the exception. The research is consistent on this across cultures and methods.

For the peak age range, the numbers are higher. Around 30% of one-year-olds still experience night wakings; around 50% of children in this age range have difficulties with sleep onset — meaning they cannot fall asleep without parental intervention such as feeding, rocking, or being held.

20–30%
Of children in the first three years of life experience clinically significant sleep problems.
Cohen et al., 2024 · cross-cultural
25–50%
Among babies aged 6 to 12 months experience problematic night wakings.
Frontiers in Neuroscience meta-analysis, 2025

A 2025 meta-analysis of 35 studies (2000–2024) confirmed that 20–30% of children demonstrate sleep–wake problems that persist through infancy and into toddlerhood. The same analysis found that consistent day–night sleep patterns typically develop between 3 and 6 months of age — explaining why the first three months are rarely the moment for structured sleep work.

In a study of 5,107 children followed from birth to age 10–11 (the Australian LSAC cohort), five distinct sleep trajectories emerged. Around 52% had no sleep problems across this period; around 7.7% had persistent sleep problems throughout middle childhood. The remaining 40% fell into mild or intermittent patterns.

Sources
  • Cohen S et al. "Sleep-related disorders in children: A narrative review." Pediatric Discovery, Wiley. 2024. DOI: 10.1002/pdi3.76. [link]
  • Gilchrist A, Aylward BS, Laine CM, Karp H. "Maturation of infant sleep during the first 6 months of life: a mini-scoping review." Frontiers in Neuroscience. 2025;19:1581325. DOI: 10.3389/fnins.2025.1581325. [link]
  • LSAC longitudinal cohort. Sleep Medicine. 2019. DOI: 10.1016/j.sleep.2019.05.010. [link]
Section 3

When sleep problems persist without help

One of the most persistent myths about infant sleep problems is that they resolve on their own. The data is more complicated.

A separate study of 250 mothers, tracking their children from 6 to 36 months, found that 21 to 35 out of every 100 children with a sleep problem before age one continued to have issues at age three.

Not all sleep problems are equivalent. Problems primarily driven by developmental transitions — the 4-month sleep architecture change, the 2-to-1 nap transition — resolve differently from problems driven by established behavioural sleep associations. The former involves a permanent change in how sleep is organised; the latter involves learned patterns that respond to consistent changes in how bedtime is managed.

41%
Of children who had a sleep problem at 8 months still had difficulty three years later.
Byars et al., Pediatrics · n=250+
7.7%
Of children had persistent sleep problems from birth through middle childhood — nearly 1 in 13.
LSAC cohort, Sleep Medicine, 2019 · n=5,107

A Canadian longitudinal study of 1,741 children found that among babies not sleeping a six-hour continuous stretch at five or seventeen months, 32.9% were still not achieving that benchmark at 29 months. Pediatric sleep researcher Lisa Meltzer summarised it bluntly: "Children don't outgrow sleep problems."

Persistent or recurring sleep problems from infancy through early childhood have been linked to higher depressive symptoms in mothers at follow-up. The child sleep problem and the parent sleep problem are not independent.

Sources
  • Byars KC et al. Cincinnati Children's Hospital Medical Center. Pediatrics. Surveyed 250+ mothers at 6, 12, 24, and 36 months.
  • Pennestri MH et al. "Uninterrupted Infant Sleep, Development, and Maternal Mood." Sleep Medicine. 2020. DOI: 10.1016/j.sleep.2020.10.005. N=1,741 Canadian children. [link]
  • LSAC longitudinal cohort. Sleep Medicine. 2019. DOI: 10.1016/j.sleep.2019.05.010. [link]
  • Lam P et al. Pediatrics. 2003. PMID: 12612272.
Section 4

Sleep, postpartum depression & maternal mental health

The relationship between infant sleep, parent sleep deprivation, and postpartum depression is bidirectional and well-documented.

A sleep disorder is not a prerequisite for PPD, but it is one of the most reliably predictive risk factors. In the 2023 BMC Psychology study, 61% also reported postpartum fatigue. These numbers are striking in their magnitude: sleep difficulty is not a subgroup experience among new mothers; it is close to universal.

3.3×
Higher odds of postpartum depression among mothers with a sleep disorder (95% CI 2.14–5.10).
Meta-analysis of 13 studies
97%
Of 1,409 postpartum women reported sleep problems; 75% showed PPD risk on EPDS.
Baattaiah et al., BMC Psychology, 2023

Persistence matters too. Children's sleep problems from infancy to early childhood predict higher maternal depressive symptoms at follow-up years later — the impact is not limited to the acute postpartum period. When a child continues not sleeping at age three, the cumulative toll on parental mental health is measurable.

Women bear a disproportionate share of postpartum sleep loss. Richter et al. (2019) found mothers' sleep was "far more affected" than fathers' regardless of breastfeeding. Mothers on extended parental leave lose more night-time sleep than those who return to work earlier — because their daytime schedule becomes more disrupted, not less.

Sources
  • Meta-analysis on maternal sleep disorder and PPD odds. OR 3.300 (95% CI 2.136–5.098).
  • Baattaiah BA et al. "The relationship between fatigue, sleep quality, resilience, and the risk of postpartum depression." BMC Psychology. 2023;11:11. DOI: 10.1186/s40359-023-01043-3. N=1,409. [link]
  • Lam P et al. Pediatrics. 2003. PMID: 12612272.
  • Richter et al. Sleep. 2019. DOI: 10.1093/sleep/zsz015. [link]
Section 5

What babies and toddlers actually need

Sleep duration recommendations are from the American Academy of Sleep Medicine (AASM) 2016 consensus statement, endorsed by the American Academy of Pediatrics (AAP). These represent ranges, not precise targets — individual variation is normal and expected.

AgeRecommended total sleep
Newborn (0–3 months)14–17 hours per 24 hours
Infant (4–12 months)12–16 hours per 24 hours (incl. naps)
Toddler (1–2 years)11–14 hours per 24 hours (incl. naps)
Preschool (3–5 years)10–13 hours per 24 hours (incl. naps)
School-age (6–12 years)9–12 hours per 24 hours

Circadian rhythms develop between 3 and 6 months. Before this window, babies have no internal clock distinguishing day from night — sleep distribution is driven by hunger and developmental state, not time.

The 4-month architectural change is permanent. Around 3.5 to 4 months, infant sleep architecture matures permanently to resemble adult sleep — distinct light, deep, and REM phases and ~45-minute cycles. The disruption (frequent wakings, short naps) resolves when a baby learns to re-settle independently between cycles — not when it is waited out.

A note on "sleep regressions": this term is not a formal clinical classification. Later disruptions at 8, 12, 18 months are real and documented, but correlate with developmental milestones (motor development, language, nap transitions) rather than with fixed calendar dates.

Sources
  • AASM / AAP Recommended sleep durations. Journal of Clinical Sleep Medicine. 2016;12(6):785–786. DOI: 10.5664/jcsm.5866. [link]
  • Gilchrist A et al. Frontiers in Neuroscience. 2025. DOI: 10.3389/fnins.2025.1581325. [link]
  • Barry ES. "What Is 'Normal' Infant Sleep? Why We Still Do Not Know." Psychological Reports. 2021;124(2):651–692. DOI: 10.1177/0033294120909447. [link]
Section 6

The help gap — awareness vs. action

Most parents who are struggling with their child's sleep do not seek professional help — not because the problem resolves on its own, but because accessible help is hard to find.

The most recent large-scale data comes from the ResMed 2026 Global Sleep Survey, which polled 30,000 people across 13 countries including the UK, Germany, and France. This gap — between knowing help exists and accessing it — is not primarily a cost issue. It is an availability issue. Sleep consultants typically operate by appointment with wait times of days to weeks; night-time crises, when parents most urgently need support, fall outside consultation hours.

66% / 23%
Said they would seek professional help for a sleep problem. Only 23% actually had.
ResMed 2026 Global Sleep Survey · n=30,000
34%
Had never sought any guidance on their sleep. Only 48% had received sleep advice from a doctor.
ResMed 2026 Global Sleep Survey

The clinical system compounds this. At Dutch youth-healthcare visits at 4 and 6 months, parental discontent with infant sleep is registered by nurses — but the visit itself averages 20 minutes and must cover growth, vaccinations, and multiple developmental checks alongside sleep.

Sources
  • ResMed 2026 Global Sleep Survey. N=30,000 across 13 markets. Conducted Dec 2025–Jan 2026. Published 3 March 2026.
  • Tandfonline (2022). "Parental Discontent with Infant Sleep During the First Two Years of Life." DOI: 10.1080/15402002.2022.2156867. [link]
Section 7

What sleep support costs across Europe

Sleep consulting is not covered by basic health insurance in any European market. The following pricing data was compiled from practitioner pricing pages across five countries in June 2026. No independent published survey of fees exists; these represent current market rates based on multiple sources per country.

CountrySingle consultationStandard packagePremium
UK£50–£150£150–£500£500–£1,000+
Germany€89–€200€290–€590up to €900
France€50–€150€150–€400€350+
Italy~€200variablevariable
Netherlands€75–€150€200–€400€500–€800+

UK: Package pricing is the most developed market. A 2-week package with daily support typically runs £250–£350. Premium consultants and in-home overnight support can reach £1,000+.

Germany: A 30-minute phone call starts around €89. Full Schlafcoaching packages — analysis, two sessions, four to eight weeks of follow-up — typically run €290–€590. €400–€900 at the premium end. Krankenkasse does not cover Schlafberatung under basic policies.

France: A phone consultation in Paris starts from €50/hour at the accessible end; specialist centres charge €150–€350 or more for an initial session.

Italy: The market is less standardised. Example: a certified consultant in Turin charges €200 per consultation (case study + 90-minute session), deductible at 19% as a healthcare expense.

Netherlands: Solo consult: €75–€150. A 2-to-3-week package with an experienced coach: €500–€800. Basisverzekering does not cover slaapcoaching; some aanvullende verzekering policies partially cover it.

Note: these are practitioner-reported market rates, not published survey data — directional reference rather than precise benchmarks. Prices vary by experience, package depth, and geography.

Section 8

Country spotlight data

The following data comes from primary research conducted in specific European countries. It is rarely cited in English-language sources and is the most differentiated material on this page.

  • 30% of Italian children under 3 have sleep problems
    Among older children (3–14), the figure is 15%. From the XIII National Congress of the Italian Federation of Paediatric Doctors (FIMP), Paestum, 2019 — gathering 1,000+ family paediatricians.
    ANSA / FIMP, 2019. Spokesperson: Emanuela Malorgio, National Coordinator, FIMP Sleep Study Group.
  • Only 47% of Italian toddlers (1–2) fall asleep in their own bed
    39% fall asleep in the parents' bed (lettone), and 13.1% change beds during the night. Source: SIPPS survey.
    SIPPS / Quotidiano Sanità. Spokespersons: Paolo Brambilla and Elvira Verduci, SIPPS.
  • Italian children sleep later and shorter than European peers
    The first Italian longitudinal study of infant sleep (n=704, 1–12 months) found typical sleep onset around 22:00 at 6–12 months.
    Journal of Clinical Sleep Medicine (AASM). DOI: 10.5664/jcsm.4114.

  • 1 in 3 French people is affected by a sleep disorder
    French people sleep an average of 1 hour 30 minutes less per night than 50 years ago.
    INSERM, cited in French National Assembly question no. 18207, 15th legislature.
  • Sleep duration at age 2 is linked to vision outcomes
    From the EDEN birth cohort (INSERM): both too little and too much nocturnal sleep at age 2 is associated with higher risk of needing glasses at preschool age — a rare long-term physical-health link to infant sleep duration.
    Rayapoullé A et al. Scientific Reports. 27 April 2021.
  • 58% of French women reported sleep troubles in the past year
    Above the general population average.
    IFOP survey, n=1,014 French adults, representative sample, April 2021.

  • 6.9% of Danish infants receive a sleep notation at the 8–9 month check
    Based on health-visitor records for 8,786 children in school year 2021/22. Sleep notations at this age were associated with poorer motor development and wellbeing at school entry.
    Virring Sørensen A et al. "Børn og unges søvn." SDU, 2023.
  • 32% of Danish adults (18–64) sleep under 7 hours per night
    Average sleep duration across the adult population: 7 hours 12 minutes.
    Statens Institut for Folkesundhed, cited in Sundhedsstyrelsen, November 2024.

  • The world's best dataset on parent sleep loss is German
    The 4,659 parents tracked in the German Socio-Economic Panel (SOEP) from 2008 to 2015 form one of the largest and most methodologically robust postpartum sleep datasets ever assembled. The 6-year non-recovery finding — and the disproportionate impact on mothers — is German data.
    Richter D et al. Sleep. 2019;42(4):zsz015. DOI: 10.1093/sleep/zsz015.

  • Peak parental discontent with infant sleep occurs at 8 months: 40% of parents
    From a Dutch study of parental discontent recorded at standard youth-healthcare visits at 4 and 6 months.
    "Parental Discontent with Infant Sleep During the First Two Years of Life." Behavioral Sleep Medicine. 2022. DOI: 10.1080/15402002.2022.2156867.
Section 9

Do babies dream? What the research shows

One of the most common questions parents ask — and one of the least clearly answered anywhere. Here is what the peer-reviewed research actually says, separated from what remains genuinely unknown.

50%
of a newborn's sleep is spent in REM — compared with 20–25% in adults. REM (rapid eye movement) sleep is the stage associated with dreaming in adults and with active brain development in infants.
Kaditis & Gozal, Children, 2022 · DOI: 10.3390/children9040523
18 hours
of daily sleep in newborns — up to 9 of which is REM. At roughly 50% REM, a newborn may experience up to nine hours of REM activity every day.
Cloudnine Care clinical review, citing Kaditis & Gozal 2022
23 weeks
gestational age when REM-like activity begins. Foetuses display REM-like brain activity from around 23 weeks, so the neural architecture for this sleep stage develops before birth.
Roffwarg, Muzio & Dement, Science, 1966
30–70 min
ultradian sleep cycle length in newborns — shorter than the 75–90 minute cycles of older infants and children, and beginning with REM rather than NREM: the reverse of adult sleep architecture.
Kaditis & Gozal, Children, 2022 · DOI: 10.3390/children9040523
Age 4–5
when children begin reporting narrative dreams. David Foulkes found children describe dreams with limited characters, plots and memories from around age four to five. Before that, even if dream-like brain activity occurs, they lack the language and memory consolidation to report it.
Foulkes D. Children's Dreaming and the Development of Consciousness, 1999

What REM sleep actually does in infants

The honest scientific position is that we do not know whether babies dream in the way adults understand dreaming. What we do know is this:

Dreaming as adults experience it involves narrative, memory and emotional processing. Infants are still building the neural architecture for all three. Their REM sleep is almost certainly doing something different from adult dreaming — it is more accurately described as developmental rehearsal. The brain is wiring itself, forming connections, processing sensory input from the day. Whether that constitutes a dream in any experiential sense is a question science cannot yet answer.

What is not disputed: REM sleep is essential for infant brain development. The unusually high proportion of REM in newborn sleep (50% versus 20% in adults) is not accidental. Roffwarg, Muzio and Dement proposed as far back as 1966 that REM predominates in early life precisely because the developing brain requires it — using the endogenous stimulation of REM to drive neural maturation at a rate waking experience alone could not produce.

In practical terms for parents: the twitching, flickering eyelids and irregular breathing you see during your baby's sleep are signs of a brain in active development. They are not a cause for concern. They are the work of sleep.

Do babies have nightmares?

True nightmares — with narrative content, recalled fear, and the ability to describe them — require memory consolidation and language development that does not exist before roughly age two. Before that point, what looks like distress during sleep is almost always a partial arousal, a normal transition between sleep stages, or a startle response. It is not evidence of a nightmare in the adult sense.

From around age two to three, as language and episodic memory develop, children begin to have and report nightmares. Night terrors — which look dramatic but are not nightmares and are not remembered — are most common between ages three and eight and are a normal feature of developing sleep architecture, not a psychological problem.

Sources
  • Kaditis A, Gozal D. "Sleep Studies for Clinical Indications during the First Year of Life." Children. 2022;9(4):523. DOI: 10.3390/children9040523. [link]
  • Roffwarg HP, Muzio JN, Dement WC. "Ontogenetic Development of the Human Sleep-Dream Cycle." Science. 1966;152(3722):604-619.
  • Foulkes D. Children's Dreaming and the Development of Consciousness. Harvard University Press, 1999.
  • Denisova K. "English translation of the first study reporting cyclical periods of increased respiration and eye motility during sleep in infants in 1926." Sleep. 2024;47:zsad219.
Section 10

Methodology and sources

How this page was assembled

Statistics were identified through searches of PubMed, Google Scholar, and institutional databases across English, French, German, Italian, Dutch, and Danish sources. Each statistic was verified against its primary source. Where a statistic is widely cited but lacks a locatable primary source, it is not included or is flagged explicitly.

Quality ratings
  • ★★★ Peer-reviewed primary study or meta-analysis — highest confidence
  • ★★ Institutional report, national congress, or reputable survey — citable with stated source
  • Industry survey — useful for scale, cite with caution

What this page does not include

  • "75% of infants experience the 4-month regression" — widely cited but unverifiable; not included.
  • Any sleep regression prevalence percentages beyond the 4-month architectural change — the literature does not support precise rates for 8, 12, or 18-month regressions.

Update schedule

This page is reviewed annually. Sleep science is an active field; recommendations on sleep duration, safe sleep practices, and behavioural sleep interventions are updated regularly by the AASM and AAP.

Section 11

Cite this page

If you are referencing statistics from this page in an article, report, or publication, please use the primary source citation listed with each statistic — not Lunio itself — as the authoritative reference. Lunio is the aggregator, not the originator, of this data.

If you wish to cite this page as a secondary source:

Lunio. "Infant & Toddler Sleep: Research and Statistics." hellolunio.com/sleep/research. Last reviewed June 2026.

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