18-Month Sleep Regression: Causes And Tips To Manage

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Like in other sleep regression stages, sleep regression in 18-month-old babies is triggered by a developmental phase where the baby’s sleep patterns change. A baby who has been sleeping well will suddenly refuse to go to sleep or wake up fussy in the middle of the night.

Though the phase is temporary and often resolves within a week, managing a baby can be more challenging during this age since they can get out of their crib and walk around. Also, they can now express their wishes more firmly than before. Therefore, during a regression episode, an 18-month-old may sit up and cry loudly, resisting going back to sleep, or they may silently walk out of their crib and roam around unsupervised, raising the risk of mishappenings.

Read on to know more about the possible causes of 18-month-old sleep regression, how long it lasts, and tips to help parents manage the regression phase.

What Causes Sleep Regression In An 18-month-old?

Changes in sleep patterns are part of growth and development. The following situations may lead to sleep regression in 18-month-old babies.

1. Growth and development

Changes in brain development may cause temporary sleep regression or changes in the usual sleep patterns of an 18-month-old. The child may have less periods of sleep or sleep pattern may change.

You may notice that phases marked by the achievement of physical and cognitive milestones are often associated with sleep regressions. You may also notice new teeth or an increase in height during the sleep regression period. The mother may specially complain of new teeth eruptions. The varying amounts of growth hormones in the baby’s body could be the reason.

2. Separation anxiety

Some babies may develop sleep regression due to separation anxiety Although it is a part of their social and emotional growth, separation anxiety may cause sleep changes in a baby if caregivers or parents leave them to sleep alone.

Your baby may sleep around you and be more  clingy than usual when they experience sleep deprivation due to fear of being away from parents (1).

3. Increased independence

Some babies may have a strong desire for independence at this age and tend to play or do something else rather than sleep. They may also try to protest by crying or through other ways when you ask them to sleep on a regular time.

How Long Will The Sleep Regression Last?

Duration of sleep regression may vary in each child. It usually lasts two to six weeks, and your baby will gradually revert to regular sleeping patterns (1). The parent generally complains to the doctor that the child does not sleep or keeps awake for hours.

A few babies may experience sleep regression for shorter periods, while some may not experience it at all.

What Does An 18-month-old’s Sleep Regression Look Like?

The baby may show the following behavior during the 18-month sleep regression.

  • Waking up at night
  • Altered sleep pattern like awake at night and sleeping in day
  • Waking up too early
  • Bedtime tantrums
  • Increased shorter naps
  • Crying and fussiness
  • Appetite changes. Not eating well
  • Clinginess and asking more cuddles

Some babies may play, call you, or talk during their bedtime. This is a normal part of development, and babies outgrow it eventually.

How Many Hours Of Sleep Is Needed For An 18-month-old Baby?

Eleven to fourteen hours of daily sleep is required for an 18-month-old baby (2). It can be split into a longer duration (10 to 12 hours) of night sleep with a few hours (two to four hours) of naps during the day.

Although sleep needs may vary in babies, all of them require enough sleep to be healthy, even when they have sleep regression. Insufficient sleep may exacerbate tantrums and cranky behavior in babies (3).

Sleep Tips For 18-month-old Babies

The following sleep tips may help your baby fall asleep during the 18-month sleep regression phase (4).

  • Let your baby follow certain bedtime routines, such as reading bedtime stories or having a bath. It can relax them and prepare them for bedtime.
  • Place the baby in the crib when they feel drowsy rather than wait for them to fall asleep in your arms. It can help them fall asleep sooner and sleep better. It may also let you observe and determine when your baby tends to fall asleep.
  • Avoid screen time a few hours before bedtime or naptime. Do not allow more than an hour of screen time in a day (5).
  • You can provide a safe and comfortable bedtime toy to the baby. It may help the baby fall asleep again if they wake up at night.
  • Adjust the sleep schedule of the baby during sleep regressions. For instance, place the baby to bed earlier at night or try extra naps during the day.
  • Feed the baby adequately before bedtime so that they do not wake up due to hunger.
  • Have a soothing night light in your baby’s room so that they can fall asleep easily.
  • You can place the baby’s crib close to your bed in your bedroom so that you are always within their line of sight. Room-sharing can make it easier for you to comfort them back to sleep if they wake up at night.

You can reinforce good sleep habits to an 18-month-old if they have sleep regression and tantrums. Set rules and limits, and encourage the baby to observe a fixed sleep schedule for both naps and nighttime sleep.

Frequently Asked Questions

1. Should I let my 18-month-old cry it out?

Many parents may not like leaving their toddlers unattended when crying. Nonetheless, the cry-it-out method could be safe and is associated with reduced fussiness at 18 months in babies (when introduced at an early age) (6).

2. What’s the worst sleep regression?

One of the most challenging sleep regressions for parents and babies may be the four-month sleep regression (usually because it is the first sleep regression in babies). During this time, the baby could be undergoing a sleep-pattern transition and physical developments (such as rolling over), which might be the reason for a sleep regression (7).

18-month sleep regression is just a phase, and there is nothing to be worried about. During this time, your baby may wake up in the middle of the night, get out of their crib and roam around, and cry aloud. Sleep regression in babies can be triggered by changes in brain development, separation anxiety, and desire for independence. Nevertheless, it is temporary and typically ends in two to six weeks. You can help your child sleep better during this phase by following a bedtime routine, bathing them, avoiding screentime and gadgets before bedtime, and placing them in their crib only when they are drowsy.

Key Pointers

  • The 18-month old sleep regression may last for two to six weeks.
  • Frequently waking up at night, increased bedtime tantrums, loss of appetite, etc., are signs of sleep regression.
  • An 18-month-old baby may need eleven to fourteen hours of sleep every day.


MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
1. 18-Month Sleep Regression; Sleep Foundation
2. Infant Sleep; Stanford’s Children Health
3. How Much Sleep Do Babies and Kids Need?; Sleep Foundation
4. The Toddler (18-ish) Month Regression: What is it and what can be done about it?;; Baby Sleep Science; Sleep Resource Center
5. Where We Stand: Screen Time; American Academy of Pediatrics
6. Ayten Bilgin and Dieter Wolke; Parental use of ‘cry it out’ in infants: no adverse effects on attachment and behavioural development at 18 months; (2020); Journal of Child Psychology and Psychiatry
7. 4-Month Sleep Regression; Sleep Foundation
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Dr Bisny T. Joseph

Dr. Bisny T. Joseph is a Georgian Board-certified physician. She has completed her professional graduate degree as a medical doctor from Tbilisi State Medical University, Georgia. She has 3+ years of experience in various sectors of medical affairs as a physician, medical reviewer, medical writer, health coach, and Q&A expert. Her interest in digital medical education and patient education made... more

Dr. Mubina Agboatwalla

Dr. Mubina Agboatwalla is a well-known pediatrician, practicing paediatrics since the last 20 years in Karachi Pakistan. She is the head of the department of Pediatrics in Karachi Liaquat Hospital, as well as her private practice in three specialist clinics in Pediatrics. She is also a Public Health Specialist specializing in preventive health including nutrition, breastfeeding and infectious diseases especially... more