The Sleep Regression Timeline by Age

Updated May 19th 2022 | timer 5  min read

The sleep regression timeline

Written By Mandy Treeby Chief Baby Sleep Consultant

One of the joys of being a parent is that every day you're experiencing your baby learn new things and develop new abilities. Like teething, sleep regressions are something your baby inevitably has to go through. While they aren't the same as growth spurts, sleep regression and growth spurts tend to coincide. Knowing more or less what to expect, you can identify sleep regressions and prepare yourself to cope with shorter nights.

No sleep regression timeline will reflect your baby's experience exactly. While many sleep regressions are unpredictable, here are the ones that are related to their development and you can reliably look out for:

4 Month Sleep Regression

8 Month Sleep Regression

12 Month Sleep Regression

18 Month Sleep Regression

24 Month Sleep Regression

4 Month Sleep Regression

By 4 months old, your baby can sleep at least five hours through the night. When suddenly she isn't lasting more than a couple of hours at a time before waking up again, it may be a four-month sleep regression. At this age, babies approach developmental milestones like sitting up and gaining more spatial awareness, giving them more reasons to wrestle with sleep.

You're likely to encounter a four-month sleep regression also because of the sleep pattern changes babies commonly experience at this age as their circadian rhythms develop.

In a medical study published in 2007, researchers looked at 194 four-month-old babies to determine what factors may be linked to sleep regression. Nearly 30 percent of the infants in the study experienced sleep regression at this age. The researchers found a noticeable link between late bedtimes (past 10 p.m.) and sleep regression in the infants.

They also suggested that delayed development of circadian rhythms can also cause sleep regression in infants at four months.

This is normal, your baby needs to develop their own circadian rhythm – that is what the 4-month sleep regression is all about! You can help them on their way by establishing a calming and  predictable bedtime routine, that happens in the same way at the same time every night.

It’s also a good idea to get a better understanding of their existing sleep patterns, for help with that check out the Smart Sleep Coach by Pampers™ App , it not only offers effortless sleep tracking tools, but it’s packed with helpful sleep video tutorials and what’s more when you track you get daily (and weekly) sleep insight reports so you can quickly get on the road to better sleep!

8 Month Sleep Regression

By 8 months old, your baby is about ready to sleep through the night. However, a sleep regression is expected around this mark because of the multiple milestones she's hitting.

If you've noticed your baby now gets fussy and emotional when she's not with you, it has to do with her development of what's called object permanence. It's the understanding that objects exist even when they can't be observed. With the attainment of this milestone comes the emotional sense your baby experiences that she's separated from you. The other change your baby is making is in her mobility. She's probably crawling around and maybe even pulling herself up to a stand.

This newfound separation anxiety may impact your bedtime routine and since babies often like to ‘practice’ their new physicals skills when in their crib sleeping – you can see how this quickly spirals into a sleep regression.

While this is a temporary sleep setback, your baby’s sleep journey will go through many of these over their first few years of life. Staying one step ahead of their sleep is a great way to confidently manage these challenging times, the Smart Sleep Coach by Pampers™ app works with you on your baby’s sleep and can be a great ally in your baby’s sleep journey.

12 Month Sleep Regression

By your baby's first birthday, she's seeing major growth in her motor skills and cognitive development. You might notice her curiosity is on fire—and it's probably fueling her to take her first steps. The huge developmental growth spurt at this age makes sleep regression common.

Having more awareness of her surroundings than ever, your 12-month-old can also become restless during in the night because of distractions. Darkening the room helps make sure she's not looking around. Playing quiet tunes can help soothe her to sleep. What matters is going through the same motions each night in a bedtime routine, so your one-year-old's body clock knows what to expect.

It’s never too late to sleep train, so if you’re struggling with your baby’s sleep or just want some helpful guidance and practical tips to get you on track, check out apps like the Smart Sleep Coach by Pampers™ . It offers a range of different tools and techniques so you can find the one that best fits with your parenting style!

18 Month Sleep Regression

At 18 months, your baby isn't only feeling curious, but also more independent and mobile than ever. As she becomes a toddler, she's testing her boundaries, including when it comes to bedtime.

Her bedtime routine might look something like taking a bath, getting pajamas on, brushing teeth and reading a story. Maintaining a consistent bedtime routine by doing the same things in the same order around the same time each night establishes a rhythm and keeps things predictable for your little one. Still, your toddler may refuse her usual nap or bedtime in favor of playing or scouting about the house.

Besides the assertion of independence, other causes of sleep regression at around 18 months is another growth surge. Developmentally, your toddler isn't just walking, but she's starting to talk and make more sense of her experiences. 

24 Month Sleep Regression

Your child is making leaps and bounds in cognitive and emotional development. Another side effect of brain development is temper tantrums. Driven by a growing sense of independence and a need to test limits, your two-year-old might be compelled to fight bedtime. Or, refuse to return to bed after waking up before the crack of dawn. Thankfully, this will pass. The more consistent your child has been with a bedtime routine in the prior months, the shorter a sleep regression at this stage is likely to last.

In a 2015 study that sampled 425 two-years-olds, 21 percent of the group regularly went to bed past 10 p.m. This group was associated with more difficulty falling asleep and shorter total sleep time, suggesting bedtime plays a crucial role in establishing a healthy sleep rhythm at 24 months. The researchers noted that a late naptime schedule could often be the culprit of late bedtimes.