Your Sleep Guide: Sleep Regressions by Age

By: Dahlia Rimmon, MS, RDN

Once you’ve survived the newborn phase and your baby starts sleeping through the night (fingers crossed!), it might feel like you’ve finally got this parenting thing figured out. But just when you’re about to celebrate your newfound evening freedom, your baby hits a new milestone and their sleep goes haywire, leaving you feeling frustrated, confused, and exhausted. Welcome to sleep regressions – a normal part of baby development, even if you’ve completed formal sleep training.

Every baby experiences sleep regressions, and they’re just a normal part of growing up, especially in that first year. Since sleep regressions can be pretty challenging (and a bit maddening!), we’re sharing everything you need to know to better tackle them, set up healthy sleep routines, and hopefully catch a few more zzz’s yourself.

What is a sleep regression?

Sleep regressions are periods of time when your baby struggles with their normal sleep routine, whether it’s staying asleep or falling asleep in the first place. During a sleep regression, your baby may refuse nap time, have frequent middle-of-the-night wake ups, or wake up at the crack of dawn. Some babies are really fussy and restless in their crib, while others switch off between happily cooing to themselves and crying. Either way, sleep regressions can be frustrating and confusing, especially for new parents who are trying to figure out why their baby won’t stay asleep.

During your baby’s first year, you can expect a few sleep regressions. They usually pop up around the 4-month, 6-month, 8-month, and 12-month marks. Some babies also experience sleep regressions after their first birthday, around 15 months, 18 months, and 24 months.

Causes of sleep regressions

If your baby normally sleeps well through the night, spotting a sleep regression can be pretty straightforward. You’ll notice signs like irritability and crying at bedtime, trouble falling asleep, waking up multiple times throughout the night, resisting naps, or a combination of a few. However, if your baby already struggles with sleep, it can be harder to tell if they’re experiencing a sleep regression or just having general sleep problems.

Most sleep regressions are triggered by one or more of the following:

• Reaching new developmental milestones like starting solids, rolling over, crawling, or walking
• Growth spurts
• Teething
• Illness
• Major changes in routine, such as moving, traveling, or starting daycare

Around the 4-month mark, babies develop their circadian rhythm, the body’s internal clock, that regulates sleep cycles and patterns. During this time, babies begin to cycle between deep and light sleep, which can lead to more wakeful periods or a sleep regression.

Sleep regressions by age

Knowing when your baby might go through a sleep regression can help you prepare for less sleep. Being prepared for a rough patch is often easier than facing it without warning. Keep in mind that every baby is different, and not all will hit a sleep regression right on schedule. Some babies experience sleep regressions early, while others have trouble sleeping a month or two late.

Here are the common sleep regressions to watch for in your baby’s first year:

4-month sleep regression

The 4-month sleep regression is the most notable sleep regression for a few reasons. It’s the first big sleep hurdle, and it can feel especially jarring when your baby suddenly starts having sleep issues out of nowhere. At this stage, babies are also developing their circadian rhythm and getting into their normal sleep pattern groove. Plus, around 4 months, your baby is going through other changes that can affect their sleep, like teething, rolling over, and strengthening their core muscles during tummy time.

6-month sleep regression

This regression may be happening because your baby has reached an exciting new milestone – starting solid foods (shoutout to our Little Bellies fruit and veggies frozen puree cubes!) While this phase is fun (and quite messy!), it can also lead to some sleep disruptions.

8-month sleep regression

Between 8 and 9 months, your baby will reach some big developmental milestones that can result in a sleep regression. They will start sitting up, scooting, crawling, or even pulling up to stand. To make nights easier, be sure to give your baby plenty of practice with these new skills during the day. This way, they’ll be worn out and ready to sleep at bedtime, rather than wanting to continue practicing at bedtime.

Around 9 months, your baby may develop separation anxiety, as they grasp the concept of object permanence. Separation anxiety is a normal part of their development, so when you put your baby down for the night, they might feel uneasy and cry because they’re uncomfortable being alone. Additionally, at this stage, they may be adjusting to other changes in their routine, like transitioning to finger foods, dropping a nap, or beginning to babble more as they develop language skills.

12-month sleep regression

When your baby turns one, you’ll see a lot of changes happening. Now officially a toddler, they may start daycare, transition from milk feeds, wean from breastfeeding, learn to walk, drop another nap, and their language skills expand too. These big changes can disrupt their usual sleep patterns.

How long do sleep regressions last?

Sleep regressions are temporary and usually only last a few weeks. Sticking to your usual sleep schedule can shorten the duration, but this isn’t true for all babies. Either way, your baby should return to their normal sleep patterns within six weeks.

Importance of establishing a sleep routine

Regardless, if you’re pro formal sleep training or prefer a more relaxed approach, establishing a sleep routine for your baby is key. Babies thrive on routine and consistency (so do we!) and giving them a solid sleep foundation is important for their sleep health (and yours!). You can start a bedtime routine right from the start and tweak them as your baby grows.

A predictable bedtime routine helps your baby know what to expect, no matter who’s putting them to bed – grandparent, babysitter, spouse, or partner – they’ll be familiar with the process.

Routines don’t have to be rigid, but they provide structure and consistency to make bedtime a smoother, less stressful activity for everyone. Over time and with practice, your baby will become more comfortable with bedtime.

You may be wondering what bedtime routines have to do with sleep regressions. Well, they’re actually closely related. Keeping your bedtime routine consistent, even during a regression or while traveling, is super important. Your baby might not fall asleep right away or may wake up frequently, but maintaining their routine helps them get through the regression faster and makes things easier for you too.

Bedtime routines can look different for every family. Some might prefer a short sleep schedule with a warm bath, milk feed, and lights out. Other families may prefer a longer sleep schedule that includes an infant massage, sound machine, and calming music. Do what works best for you and your baby and consider their age as you plan.

Here are a few examples of bedtime routines:

Bedtime routine #1

6:00 PM: Warm bath

6:15 PM: Infant massage and pajamas

6:25 PM: Dim lights and milk feed

6:40 PM: Burp and lullaby

6:45 PM: Bedtime

Bedtime routine #2

5:45 PM: Read books

6:00 PM: Warm bath

6:10 PM: Pajamas

6:15 PM: Milk feed

6:30 PM: Bedtime

Bedtime routine #3

6:15 PM: Warm bath

6:30 PM: Play calming music and infant massage

6:40 PM: Skin-to-skin milk feed

7:00 PM: Burp and pajamas

7:15 PM: Read books and lullaby

7:30 PM: Bedtime

Tips for parenting through sleep regressions

In addition to setting up a bedtime routine, here are some other tips to help you get through sleep regressions:

• Encourage self-soothing: Teach your baby to soothe themselves to sleep.
• Practice new skills: Give your baby plenty of opportunities during the day to practice sitting up, crawling, or whatever new skill they’re working on.
• Create a good sleep environment: Make their room dark with blackout shades, use a sound machine to block out noises, and dress them in breathable fabrics to keep them cool and comfortable.
• Limit screen time: Avoid screens, especially before bed.
• Engage in calming activities: Read books, play relaxing music, or cuddle together before bed time.
• Adjust nap times: If your baby is having trouble falling asleep at night, they might be napping too much during the day. Consider dropping or shortening naps.
• Manage expectations: Recognize that everyone’s sleep might be disrupted during a sleep regression. If possible, reschedule any plans that might be hard to manage if you’re tired.
• Address separation anxiety: If your 9-month-old is extra clingy at nap or bedtime, shower them with attention during the day to give them the comfort they need.

Mistakes when managing sleep regressions

Here are some common pitfalls to avoid during sleep regressions:

• Nursing or bottle-feeding your baby to sleep: This can prevent your baby from learning to fall asleep on their own, which is especially important during sleep regressions.
• Rocking your baby to sleep: Similar to feeding, this can create a dependency that makes it harder for them to self-soothe.
• Skipping your sleep schedule: Whether you’re traveling, your baby is sick, or going through a regression, a consistent sleep schedule and bedtime routine is key.
• Getting frustrated during wake-ups: It’s tough but try to stay calm and patient when your baby wakes up in the middle of the night.

Sleep regressions are tough for everyone, we get it! Just remember, all parents go through it and we’re in this together. Stay calm, stay strong, and soon enough, you’ll all be back to snoozing through the night in no time.