Sleep Regression Agess — What Are They, and When Will They End?

Sleep regression refers to a temporary phase where babies or toddlers experience disrupted sleep patterns, such as more frequent night wakings and shorter naps. These disruptions are often tied to developmental milestones, increased awareness, and physical growth.Sleep regression is a temporary disruption in a baby’s sleep patterns, often caused by developmental milestones or physical growth.

Key Ages & Characteristics:

Sleep regressions often align with developmental milestones and typically occur at predictable ages. For example, a 1-month-old baby sleep regression may be linked to adjusting to life outside the womb. By 2 months, babies might experience a 2-month-old baby sleep regression, especially during a 2.5-month sleep regression or as an 8-week-old suddenly not sleeping due to overstimulation. Around 10 weeks, a sleep regression can emerge as babies adapt to longer stretches of sleep, with an 11-week-old baby sleep regression showing similar signs. At 5 months, sleep regression signs become more noticeable, often marked by frequent wakings and trouble settling between cycles.

0–3 months: Frequent wakings due to feeding and developing circadian rhythms.
4 months: Transition to mature sleep patterns; waking every 3–4 hours is common.
6–9 months: Motor skill milestones, teething, and separation anxiety.
12–18 months: Transition to one nap and growing independence.
2–3 years: Bedtime resistance and dropping naps.
4–6 years: Sleep disruptions due to emotional growth or life changes like school.

Signs of Sleep Regression:

Increased night wakings and shorter naps.
Clinginess, fussiness, and resistance to bedtime
If your baby starts resisting naps or waking more at night, they might be going through a sleep regression.

Managing Sleep Regression:

Stick to consistent routines, adjust nap schedules, and encourage self-soothing. Offer gentle comfort but avoid forming new sleep associations.

Kim Says: “Sleep regressions can feel exhausting, but they’re temporary. With patience, structure, and reassurance, you can help your baby—and yourself—get through it.”

Why Do Sleep Regressions Happen?

According to pediatrician and child development expert, Dr. T. Brazelton, sleep regressions are a normal phase of disorganization in a baby’s body and brain that happen right before, or in the midst of exciting developmental growth. You can think of it this way: learning how to sit up or stand or to see an object and know its name are such hard tasks that your baby’s body and brain can’t stay on top of their other jobs. Sleeping, eating, and even their mood kind of go off the rails! When their new skill becomes more familiar, your baby will be able to keep all of it together better and sleep will settle down again.

How Long Will This Last?

Sleep regressions usually last between 2-6 weeks. The good news is that most babies don’t experience every sleep regression between birth and 3 years old. Some developmental milestones are more exciting and more difficult than others for different babies.

What are the Typical Ages when Regressions Occur?

Sleep regressions don’t happen at exact ages but they do happen when babies start to change in some important ways developmentally. These developmental ‘leaps’ — as Wonder Weeks calls them — typically happen around specific ages. However, your child may experience them at different times than other babies their age.

4 Month Sleep Regression

While not all babies will experience all the sleep regressions, most families find themselves struggling with frequent night wakings between their baby’s 4th and 5th months. In this developmental window your baby is starting to see themselves as separate from others — even you! This is also when their sleep patterns begin to change and their deep and light sleep cycles become more distinct. Without going into too much sleep science, your baby is likely sleeping in 45-50 minute cycles. Even babies who were sleeping well can start to struggle at the transition from light to deep or deep to light sleep. What does that mean? Frequent night wakings are really common during this sleep regression and you may find yourself holding, rocking, and shushing your baby often to calm them down.

Experiencing your first real regressions?
Read: 4 Month Sleep Regression – Tips To Soothe Your Baby

7 Month Sleep Regression

The sleep regression that occurs between 6 and 7 months old is another one most babies experience in some way or another. Babies are making exciting developmental strides that you can see during this phase. Many 6-7 month-olds are learning to sit up on their own and some may even begin creeping or crawling along on their belly. Their eating habits are changing as you begin to explore more solid foods and they start using their pincer grasp to pick food up and feed themselves.

In the middle of the 7 month sleep regression?
Read: The 7 Month Sleep Regression — What To Expect

9 Month Sleep Regression

Just like at 6-7 months, the 8 to 9 month sleep regression is due to a lot of brain development. Your baby may be starting to crawl, scoot, and even pull themselves up to standing. Many babies at this age struggle at nap time and even in the night as they practice standing up in their crib without knowing how to get down. Your baby is also beginning to put things into categories, which is the start of learning language. For example, they begin to know that something is a ball no matter what color or size it is. All of this is exciting and can keep even the calmest, mellowest babies up at night and during naptime.

Need to know more about the 9 month regression?
Read: The 9 Month Sleep Regression — When Your Baby Stops Sleeping

12 Month Sleep Regression

Babies around one year are adding even more skills to their tool box. The language that was just conceptual or just noise a few months ago is becoming recognizable to adults around them. They may be able to say ‘mama’ and ‘dada’ — though not always for the correct person — and even say one or two additional words. They’ll soon be able to walk and are practicing by pulling themselves up on EVERYTHING and even taking a few steps holding your hand or a piece of furniture. What does all of this have to do with their sleep? Your baby may be waking early from their naps or even refusing them altogether. Babies that were sleeping well through the night may be waking frequently again.

15 Month Sleep Regression

At 15 months your toddler may be in the midst of two major changes — walking independently and transitioning to one nap per day. Babies this age seem to be on the move CONSTANTLY as they practice walking (and falling) everywhere! Some are so focused on practicing this exciting new skill they may have trouble quieting down to sleep. The transition from two naps per day to one can also be bumpy. Less daytime sleep can leave your baby overtired at bedtime and harder to get to bed smoothly. Being overtired can even contribute to more night waking.

Is your young toddler waking up AGAIN?
Read: The 15 Month Sleep Regression — What to Expect

18 Month Sleep Regression

Your toddler dropped from two naps to one and you thought you were in the clear. At 18 months you may find yourself waking, from out of nowhere, to a shrieking baby in the night. Perhaps you’re even fighting to get that one nap during the day, AGAIN! Children begin to really expand their language skills around this age and are becoming more independent with their play, movement, and eating. This increased independence can also equal an increased will, so you may notice your toddler experimenting with tantrums during the day and at sleep time.

Is the 18-month sleep regression on your mind?
Read: 18 Month Sleep Regression: How To Get Your Toddler Back To Sleep

sleep regressions — Toddlers understand that they have a choice about things and many parents find their child begins experimenting with the power of this choice at bedtime and at naps.

2 Year Sleep Regression

Your toddler’s language is now getting more sophisticated and he’s experimenting with new words and phrases including “No!” During this period of development he’s also learning about consequences and cause and effect. For example, what happens when Daddy asks me to sit down at the table and I yell, “No”? Toddlers at this age understand that they have a choice about things and many parents find their child begins experimenting with the power of this choice at bedtime and at naps.

Maybe “terrible twos” have a sleep regression to blame!
Read: The 2-Year Sleep Regression – How to Get Your Child Back to Sleep

3 Year Sleep Regression

As children leave the toddler phase, some may experience a final sleep regression around three. As your 3-year-old’s world gets bigger, fears and phobias can crop up and be especially upsetting at night. Bad dreams, requests to check the closet and insisting that someone stay with them at bedtime are common at this age. Three is also the age when many families embark on potty training. The logistics of dropping diapers at night and the developmental leap it is for children to be aware of their need to use the bathroom can disrupt their sleep.

Three and…up all night?
Read: The 3 year Sleep Regression — What to Expect From Your Preschooler

Types of Sleep Regressions

Newborn Sleep Regressions

Newborns experience disrupted sleep in their first months as they adjust to life outside the womb. Factors like feeding schedules, overstimulation, and short sleep cycles frequently cause wakefulness. As they develop regular sleep-wake cycles, sleep regressions are common.

Infant and Toddler Sleep Regressions

Kim Says: “Less sleep for your baby obviously means less sleep for you, too. At a time when her demands on you for comfort, nursing or eating, and attention during the day are high, these sleep interruptions can equate to some tough moments of parenting.”

Infants often experience sleep regressions around major developmental milestones. Signs include frequent night wakings, short naps, and increased clinginess during the day. Toddlers, especially around 18 months and 2 years, experience disruptions due to increased independence, developmental milestones like walking, and transitions like dropping naps.

Parents Say:

Perla – June 7, 2024: “Help… I’m having such a hard time with my 5mo who just won’t nap or sleep like before. Is this part of the 4-5 month sleep regression phase?”

Severity of Sleep Regressions

The Worst Sleep Regressions

The 4-month sleep regression is considered the most challenging by many parents. Babies transition to more mature sleep patterns, resulting in frequent waking and difficulty falling back asleep. The 6-month, 10 month, and 12-month sleep regressions are also significant and often coincide with milestones like motor skills and separation anxiety.

Kim Says: “Frequent night wakings are really common during this sleep regression, and you may find yourself holding, rocking, and shushing your baby often to calm them down.”

Parents Say:

Anonymous member – June 7, 2024: “My son was an amazing sleeper between 3-6 months, and now, at 8 months, he wakes every hour. Did this happen to anyone else?”

When Does It Start and How Long Does It Last?

Sleep regressions generally happen during big developmental changes, though timing varies by child. Common stages include 4 months, 6 months, 8-10 months, 12 months, 18 months, and 2-3 years. (1-Cleveland) During these phases, your baby is growing mentally and physically, which can disrupt their usual sleep patterns.

Kim Says: “You can think of it this way: learning how to sit up or stand or to see an object and know its name are such hard tasks that your baby’s body and brain can’t stay on top of their other jobs. Sleeping, eating, and even their mood kind of go off the rails! When their new skill becomes more familiar, your baby will be able to keep all of it together better, and sleep will settle down again.”

Parents Say:

Caroline – June 13, 2024: “I am reading the book and had a question. Is there a certain age when sleep regressions tend to lessen? My little one is 9 months, and it feels endless.”

Signs of Sleep Regression

You might notice these signs of sleep regression:

Increased night wakings.
Shorter naps, leaving your baby still tired.
Extra clinginess and fussiness during the day.
Resistance to bedtime or nap time.
Restlessness and difficulty settling into routines.
Witching hour, where your baby becomes fussy in the late afternoon or early evening.

Kim Says: “Your baby may be waking early from their naps or even refusing them altogether. Babies that were sleeping well through the night may be waking frequently again.”

Parents Say:

Bethany – June 28, 2024: “Quick question. It’s been a long time since I posted, and we’re struggling with frequent night wakings again. Anyone else experiencing the same with a toddler?”

Handling Sleep Regressions

Sleep regressions can feel overwhelming, but with consistency and small adjustments, you can help your child—and yourself—navigate this temporary phase.

Key Strategies:

Stick to a Consistent Routine: Maintain a predictable bedtime routine with calming activities like reading, a warm bath, or soft music to signal it’s time to wind down.
Adjust Wake Times: Monitor your child’s active awake time to ensure they aren’t under- or overtired, which can affect their ability to fall and stay asleep.
Encourage Self-Settling: Gradually reduce assistance during nighttime wake-ups to help your child develop independent sleep habits.
Evaluate Nap Schedules: Ensure the number and length of naps align with their age. Adjust as needed to prevent overtiredness or excessive daytime sleep.
Provide Additional Comfort (Without New Habits): Offer verbal reassurance or gentle pats if your child is particularly fussy, but avoid creating new sleep associations like rocking or feeding.
Track Sleep Patterns: Use a simple sleep tracker to identify changes in their sleep needs and adjust schedules accordingly.
Be Patient: Sleep regressions are temporary. Staying consistent and maintaining healthy sleep habits will help your child adjust over time.

What Causes Sleep Regression?

Sleep regression is commonly caused by:

Developmental Milestones and Growth Spurts: As babies reach milestones like rolling and talking, sleep often gets disrupted. Teething, separation anxiety, and hunger during growth spurts also lead to more night wakings. (6-Amir)

Parents Say:

Anonymous member – June 14, 2024: “Both my five-year-old and almost four-year-old have regressed big time with sleep, especially during any life changes. Could use some advice for handling this while staying consistent.”

Differentiating Sleep Regressions from Other Issues

leep regressions can resemble other issues like teething or illness, but identifying the cause is essential for addressing your child’s needs effectively.

Quick Comparison:

Sleep Regressions: Last 2-6 weeks, tied to developmental milestones like sitting or crawling, and typically improve on their own.
Teething: Disruptions align with symptoms like swollen gums, drooling, and chewing on objects, often easing with pain relief.
Illness: Accompanied by fever, congestion, or other signs of discomfort, with sleep normalizing after recovery.

Observe patterns. If disruptions persist beyond six weeks or include unusual symptoms, consult a pediatrician.

Typical Sleep Patterns vs. Sleep Regressions (4 Months to 3 Years)

Here’s a quick comparison between typical sleep patterns and regressions, based on American Academy of Pediatrics recommendations. (3-Paruthi)

Age Group	Typical Sleep Patterns	Sleep Regressions
Infants (4-6 months)	12-16 hours/day and night	Frequent night wakings, short naps, and increased fussiness.
Infants (6-9 months)	10-12 hours of nighttime sleep, 2-3 naps totaling 2-4 hours	Nighttime awakenings and resistance to naps.
Infants (9-12 months)	10-12 hours of nighttime sleep, 2 naps totaling 2-4 hours	Disrupted sleep due to milestones like standing or walking.
Toddlers (1-2 years)	11-14 hours/day	Increased night wakings and nap resistance during transitions.
Preschoolers (3-5 years)	10-13 hours/day	Night wakings, difficulty falling asleep, and disruptions from developmental milestones.

Parents Say:

Rodrigo – September 10, 2020: “Hi, my baby is 15 months, and we can get her down for naps, but nighttime has become a struggle. Any tips for keeping her in her crib longer?”

Nicola – September 10, 2020: “Hi all – I have a 7-year-old boy who’s having trouble staying asleep. We’ve tried a lot of routines, but this feels like another regression.”

FAQ

Q: How do I know if my baby is in a sleep regression?

Ans: Sudden night wakings, shorter naps, and fussiness are signs of sleep regression, often linked to developmental milestones.

Q: Do All Babies Have Sleep Regressions?

Ans: Not all babies experience noticeable regressions, but it’s common for many to have disruptions around major developmental stages.

Q: What not to do during sleep regression?

Ans: Avoid creating new sleep habits like rocking or feeding to sleep. Stick to routines and try not to rush in immediately when your baby wakes up.

Q: Can a 4-year-old have sleep regression?

Ans: Yes, big changes like starting school or new routines can trigger regressions in a 4-year-old.

Closing Guidance – “Remember: It’s Just a Phase!”

Kim Says: “No matter what ages your baby or toddler experiences their sleep regressions, it takes a lot of work from you to get through it smoothly… remember that this phase is temporary and a normal part of your baby growing up into a bigger, bolder, and older child!”

Citations

Cleveland Clinic. “Infant Sleep Regression: What Parents Need To Know” https://health.clevelandclinic.org/the-4-month-sleep-regression-what-parents-need-to-know
SADEH, A., MINDELL, J.A., LUEDTKE, K. and WIEGAND, B. (2009), Sleep and sleep ecology in the first 3 years: a web-based study. Journal of Sleep Research, 18: 60-73. https://doi.org/10.1111/j.1365-2869.2008.00699.x
S. Paruthi, L. Brooks, C. D’Ambrosio, W. Hall, S. Kotagal, Robin M. Lloyd, B. Malow, K. Maski, C. Nichols, S. Quan, C. Rosen, M. Troester and M. Wise. “Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement of the American Academy of Sleep Medicine..” Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine, 12 6 (2016): 785-6 . https://doi.org/10.5664/jcsm.5866.
McGraw, Kate, Robert Hoffmann, Chris Harker and John H. Herman. “The development of circadian rhythms in a human infant.” Sleep 22 3 (1999): 303-10. https://doi.org/10.1093/SLEEP%2F22.3.303
Sleep Regulation, Physiology and Development, Sleep Duration and Patterns, and Sleep Hygiene in Infants, Toddlers, and Preschool-Age Children. Bathory E., Tomopoulos S.(2017) Current Problems in Pediatric and Adolescent Health Care, 47 (2) , pp. 29-42. https://doi.org/10.1016/j.cppeds.2016.12.001
Amir Ali Mazandarani and Mahdi Zare Bahramabadi. “What is the Sleep Pattern of Infants and Toddlers in the Iranian Population? An Epidemiological Study.” Sleep Science, 16 (2022): e284 – e293. https://doi.org/10.1055/s-0043-1772804.
Rivkees, Scott A. “The Development of Circadian Rhythms: From Animals To Humans.” Sleep medicine clinics vol. 2,3 (2007): 331-341. doi:10.1016/j.jsmc.2007.05.010