Complete guide to baby sleep
Everything you need to know in one place — from the ideal routine to the 4-month regression, from white noise to personalized stories. Science-based advice, told simply for tired parents.
Sleep isn't a problem you "solve" — it's a journey you navigate together with your baby. This guide synthesizes 7 thematic articles into a single overview. Use it as a starting point, then dive deeper into the areas where you need more.
All the advice here is put into concrete practice in the Lulla app — free, no ads, no mandatory subscriptions. Smart timer, sleep score 0-100, 120 personalized stories, 50 ambient sounds and parent-to-parent sharing.
- 00
Not sleeping right now? Start here
The three questions that separate a real problem from a schedule problem, the grid that tells you what their wake-up time means, and the table that links the exact symptom you can see to the page that solves it. If you're here at 23:00, read only the first two sections.
- First check whether the 24-hour total is inside the range for their age
- The wake-up time tells you the cause: 40 minutes, middle of the night or 5 in the morning
- Six windows where sleep breaks because of development, not because of you
- What to do tonight, in 15 minutes
- 01
Evening routine — the foundation of any good sleep
In a study of 10,085 mothers across 14 countries, babies with a nightly routine fell asleep in about 18 minutes on average, against 24 without one, and spent 19 minutes awake at night instead of 67. The link is gradual: every extra evening you keep the routine shows up in the numbers.
- Warm bath at 6:30 PM — triggers the thermal sleepiness signal
- Gentle 5-minute massage with lavender to calm the nervous system
- Story or song — your voice is the best lullaby
- Put them in the crib drowsy but awake to learn self-soothing
- 02
How much they sleep by age, from newborn to age 3
The 14-17 hours for 0-3 months come from a vote by a National Sleep Foundation expert panel, which considers that 11-19 hours can also be fine. When they're measured, newborns often sleep less than parents think. What matters more is whether the baby is feeding, wetting diapers, growing and waking easily.
- 0-3 months: 14-17 hours/day recommended; 11-19 hours can be fine
- 4-11 months: 12-15 hours/day (WHO: 12-16), 2-4 naps + night
- 1 to 3 years: 11-14 hours/day (1-2 naps + night)
- In a newborn, the warning sign is a baby who is hard to wake or feeding little, not the number of hours
- 03
4-month sleep regression — pure biology
Suddenly, the baby who slept 6 hours straight wakes up every 2 hours. You haven't done anything wrong — their brain is going through the biggest reorganization since birth. Cycles are maturing from 2 to 4 phases.
- We found no study that measured how long it lasts
- Consistency with the routine is THE KEY — even when it doesn't seem to work
- Don't start a new settling method on the worst nights, and don't start one with crying before 6 months
- Don't introduce new habits (nursing to sleep, rocking) that you'll have to unlearn later
- 04
White noise — what's proven and how loud
In a randomized study of 40 newborns aged 2–7 days, 80% fell asleep within the first five minutes with white noise, against 25% without. It's from 1990, it hasn't been repeated, and it measured falling asleep, not all-night sleep. At home, the part that matters is the volume: at maximum, at 30 cm, machines and apps average above 70 dBA.
- Outside the crib and as far away as possible, at the lowest volume: under 50 dB at your baby's head
- Volume matters more than distance
- White, pink or brown: no one has compared them in babies; choose a steady sound with no peaks
- Only for a short time, as the American Academy of Pediatrics advises: for example, switched off once your baby is asleep
- 05
Bedtime stories with the baby's name
A child hears their own name every 30 seconds and connects emotionally. 120 original stories in your language, personalized with your baby's name. 6 themes that work for all ages.
- Stars and constellations — cosmic calming
- Forest and animals — therapeutic stories
- Ocean and waves — natural rhythm
- Moon and clouds — meditation for the little ones
- 06
Sleep score — measure what matters
A daily 0-100 score calculated from 6 components: duration, bedtime consistency, night/day ratio, wake-ups, quality rated by you, and mood on waking. See trends, not just moments.
- The "Rhythm" component shows bedtime consistency
- Under 30 min variation = goal achieved
- Personalized daily tip for improvement
- Professional PDF export for your pediatrician
- 07
Parent sharing — sleep is a team effort
With Lulla, both parents see the same live data, from different phones. A 6-character invite code and you're done — your partner has access to profiles, sessions and statistics.
- Generate a code from Settings → Sharing
- Automatic live sync between devices
- All new sessions appear instantly for both
- Baby profiles and full history shared
Lulla does all of this
The free app that implements everything you've read here. Smart timer, sleep score, personalized stories, ambient sounds and parent sharing. No ads.
Available on Android and iOS
Sources
The figures quoted in this guide come from the studies below. The 2015 study shows an association, not proof of cause. This information is educational and does not replace advice from your pediatrician.
- Mindell JA, Li AM, Sadeh A, Kwon R, Goh DYT. Bedtime routines for young children: a dose-dependent association with sleep outcomes. Sleep. 2015;38(5):717–722.
- Mindell JA, Telofski LS, Wiegand B, Kurtz ES. A nightly bedtime routine: impact on sleep in young children and maternal mood. Sleep. 2009;32(5):599–606.
- Spencer JA, Moran DJ, Lee A, Talbert D. White noise and sleep induction. Archives of Disease in Childhood. 1990;65(1):135–137.
- Hugh SC, Wolter NE, Propst EJ, Gordon KA, Cushing SL, Papsin BC. Infant sleep machines and hazardous sound pressure levels. Pediatrics. 2014;133(4):677–681.
- Hong SA, Kuziez D, Das N, Harris D, Brunworth JD. Hazardous sound outputs of white noise devices intended for infants. International Journal of Pediatric Otorhinolaryngology. 2021;146:110757.
- Philbin MK, Robertson A, Hall JW 3rd. Recommended permissible noise criteria for occupied, newly constructed or renovated hospital nurseries. Journal of Perinatology. 1999;19(8 Pt 1):559–563.
- Balk SJ. How Noise Affects Children. HealthyChildren.org, American Academy of Pediatrics. 2023.
- American Academy of Pediatrics — Safe Sleep
- Hirshkowitz M, Whiton K, Albert SM, Alessi C, Bruni O, DonCarlos L, et al. National Sleep Foundation’s sleep time duration recommendations: methodology and results summary. Sleep Health. 2015;1(1):40–43.
- World Health Organization — Guidelines on physical activity, sedentary behaviour and sleep for children under 5 years of age
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