Navigating the different sleep regression ages can make even the most patient parent feel exhausted. One day, your baby is sleeping through the night. The next day, they’re suddenly waking up every hour. No doubt, it feels like all your hard work was for nothing!
But don’t worry. It doesn’t mean you’ve failed. Sleep regressions are a normal part of your baby’s growth and development and are a sign that you’re doing things right.
With that in mind, let’s break down some of the most common sleep regression ages and explore the causes behind each. We’ll also highlight key signs to look for and share practical, expert tips to help you manage these sudden changes in your baby’s sleep.
Key Takeaways
Table of contents
What is a sleep regression?
A sleep regression is a common and temporary period when a baby or toddler who was sleeping well (taking good naps, sleeping through the night) suddenly starts having serious trouble with sleep.
It can feel like a huge step backward, making you think you’ve done something wrong or that the sleepless nights will never end.
But a regression is actually a positive sign of growth! These disruptions usually happen around certain baby sleep regression ages because your child's brain is so busy learning new, amazing skills that it can’t “focus” as well on sleeping.
For example, when your baby learns to crawl, their brain activity goes into overdrive. They might be eager to practice their new skills (like maneuvering to all-fours) in the crib instead of resting.
The most important thing to remember is that sleep regressions are temporary. They’re tied to specific developmental leaps, and they usually only last a few weeks. Once your child masters that new skill, their sleep patterns should return to normal.
Baby sleep regression ages
4 months
The 4-month sleep regression is the first and most-talked-about regression because it’s a dramatic and permanent change in how your baby sleeps.
Signs
- Naps become suddenly short (30-45 minutes)
- Night waking increases dramatically and can occur every one to two hours
- Difficulty falling back to sleep without help (rocking, holding, feeding)
Causes
The 4-month mark is when your baby’s sleep pattern matures. They move from two simple sleep stages (awake/asleep) to four adult-like stages, which include lighter sleep (REM) and deep sleep.
The transitions between these four stages bring them closer to their wakeful state and make it much easier for them to become aware of their surroundings, which is why they wake up so often throughout the night.
6 months
While not as common as the four- and eight-month regressions, your baby may hit a snag around six months because they’re teething and might also be starting to roll over and sit up.
Signs
- Waking up and immediately practicing sitting or rolling
- Getting “stuck” in an uncomfortable position and crying for help
- Increased drooling and fussiness from teething
Causes
The main cause of this change in sleep patterns is the sudden mastery of advanced motor skills. They are so excited about their newfound abilities that they want to practice them instead of going to sleep.
This, combined with teething, can lead to many restless nights.
8-10 months
The next sleep regression (which can happen between 8 and 10 months old) is similar to the 4-month regression in that it involves major physical and mental breakthroughs that can keep your child up at night.
Signs
- Intense crying or fussing when you leave the room
- Standing up and bouncing in the crib instead of lying down
- Waking and calling for you repeatedly during the night
Causes
One of the biggest causes of this sleep regression is the fact that your baby now understands object permanence. That means that they know you exist even when they can’t see you. This leads to anxiety when you leave, making bedtime tough.
Another major cause of this sleep regression is that your baby is learning to move in all sorts of new ways (crawling, pulling to stand, cruising along furniture) and they want to practice, practice, practice.
12 months
The 12-month regression is often more about the switch from two naps to one, but your baby’s nighttime sleep patterns can be affected as well.
Signs
- Resistance to the afternoon nap
- Fighting both naps sometimes
- Waking up very early in the morning
Causes
Many babies drop the second nap between 12 and 18 months, but some may need two naps for longer.
Trying to force a nap can cause overtiredness, but dropping it too soon does the same. This transition creates temporary chaos and confusion for you and your little one.
In addition, many toddlers take their first steps and say their first words around this time, putting their brains and bodies into overdrive.
18 months
The 18-month sleep regression is often the precursor to the “Terrible Twos” and can turn into a battle of wills between you and your little one.
Signs
- Using their newfound verbal skills to protest with "No," "Up," and/or "Out!"
- Strong, intense tantrums at bedtime or nap time
- Trying to climb out of the crib
-
Teething pain from the two-year-old molars
Causes
At 18 months, your child may start to exert and test their independence, and refusing to sleep is one of the few things they can control.
They’re also experiencing a big physical milestone: Molars! The large 18-month back teeth often break through at this time and can be very painful.
24 months
This 24-month sleep regression happens as your little one becomes a full-fledged toddler, often coinciding with a move from the crib to a toddler bed.
(Note: Many children transition to a toddler or twin bed around age 3 or later, but it depends on your child’s readiness. If they’re climbing out or have outgrown their crib, it may be time to make the switch sooner.)
Signs
- Fear of the dark, asking for water, or wanting "just one more story"
- Nightmares or night terrors (often linked to their big vocabulary)
- Repeatedly getting out of bed (if they've transitioned into a toddler bed)
Causes
While the previous five sleep regressions were influenced by both physical and mental developments, the 24-month regression is almost completely dominated by the mental side.
Your little one’s imagination is developing, and this can lead to new fears and bad dreams. In addition, they’re starting to grapple with big emotions, trying to process complex feelings, and looking for ways to continue testing the boundaries that you’ve set.
How to cope with sleep regressions
Coping with a sleep regression requires a mix of patience and smart strategies. The key is consistency. Keep your regular bedtime and nap routines (like a bath, book, and song) exactly the same. This predictability is very calming for your baby.
When dealing with wakings throughout the night, wait a few minutes before rushing in, giving your baby a chance to resettle themselves. When you do go in, be quick and boring. Offer comfort, but avoid introducing new stimulation (like rocking or feeding) that can turn into habits.
Also, make sure their room is dark, cool, and quiet to set the stage for good rest. Finally, prevent overtiredness by sticking to age-appropriate wake windows during the day.
Survive baby sleep regressions with Newton.
Coping with the various sleep regression ages can feel overwhelming, but remember that these periods are temporary signs of healthy cognitive and physical development in your child.
By prioritizing a consistent routine, recognizing the signs of overtiredness, and offering comfort without creating new, hard-to-break habits, you’ll both get through these phases.
Products like the Newton Crib Mattress and fitted sheets help support a safe, clean sleep space, which can contribute to better rest.
While a new mattress won't stop the developmental leap, it’s a powerful step in helping your baby sleep through the night again. Stay patient, stay consistent, and know that restful nights are just around the corner!
Ready to give your baby the safest and most comfortable sleep environment possible? Click here to learn about Newton crib products and to start your 100-night trial.
Frequently asked questions
How can I tell if it’s a sleep regression or teething/illness?
Sleep regressions involve sudden and sustained poor sleep without other major symptoms. Teething/illness usually includes other major symptoms, such as fever, drooling, or congestion.
If your baby has a fever of 100.4℉ or higher, see a doctor right away. If drooling or congestion lasts for more than a few days, have your little one checked out by a doctor to see if they’re teething, have allergies, or have caught a cold.
Should I try sleep training during a regression?
No, it’s not a good idea to try sleep training during a regression. A full sleep training method like Ferber or Extinction can be too stressful for both you and your baby during a sleep regression.
Instead, focus on comforting your little one during the 2-6 week regression period. Once the developmental leap has passed and your baby is back to their normal, happy self, then you can return to or start sleep training.
What’s the difference between a sleep regression and a growth spurt?
It’s super easy to mistake a growth spurt for a sleep regression (and vice versa) because they can often happen at the same time.
A sleep regression is a change in your baby’s ability to fall or stay asleep, often because their brain is too busy processing new mental and/or physical skills. A growth spurt, on the other hand, is when your baby is growing rapidly and needs more food (including more night feedings).
If the only issue is hunger, it’s likely a growth spurt. But if your little one is awake, happy, and practicing a new skill (like sitting up), it’s more likely a sleep regression.
