The Ultimate Guide To Understanding and Navigating Baby Sleep Regressions

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As parents of little ones ranging in age from in utero to elementary school, our team faces every sleep challenge under the sun. While we're experts on gear, we are decidedly not experts on sleep - but we know those who are. Courtney Zentz, Founder of Tiny Transitions is the real deal. We interviewed Courtney with our most pressing questions about sleep regressions, what causes them, and how to fix them - at every age. We love Courtney's positive, practical, and realistic take on baby sleep (and parent sleep!) and we think you will too.

What is a sleep regression?

Sleep regression is a period of time when a baby who has been sleeping well suddenly starts waking up frequently, has trouble falling asleep, or changes their sleeping patterns without a clear reason. This can be incredibly stressful for parents who thought they had finally mastered having a baby that sleeps through the night.

What triggers a sleep regression? Several factors contribute to infant sleep regressions, including developmental milestones, teething, illness, or changes in the baby’s environment. Your baby's brain is growing rapidly, and these periods of wakefulness could be necessary for developmental gains.

For instance, if teething is disrupting sleep, consult your pediatrician about safe ways to alleviate pain. Keep the bedtime routine consistent, create a soothing sleep environment, and offer comfort without creating new sleep associations that you'll have to undo later.

What are the most common sleep regression ages?

The most common sleep regressions usually occur at specific ages in a baby's development and often coincide with significant milestones or changes. Here's a list of the most common sleep regressions little ones - and parents! - face.

4-Month Sleep Regression: When baby is around 4 months old, parents may notice their first significant sleep regression. At this age, babies become more aware of their surroundings, and their sleep cycles start to mature, shifting from the simpler newborn sleep patterns. You might notice that your baby has difficulty falling asleep, wakes up more frequently in the middle of the night, and may have shorter naps.

6-Month Sleep Regression: Around 6-8 months old, babies become more mobile. They are learning to crawl, pull themselves up, and may even start cruising around furniture. These new skills are mentally and physically stimulating, and can cause disruptions in sleep. Your baby may resist bedtime, wake up more often with fussing, and be difficult to soothe back to sleep.

12-Month Sleep Regression: This sleep regression often coincides with a growth spurt, or a surge in physical abilities like walking or increased social awareness. Again, these are big developmental leaps that can create sleep problems. Naps might become battlefields, and your baby might wake up more frequently at night.

18-Month Sleep Regression: At around 18 months of age, toddlers often experience separation anxiety, leading to night wakings and difficulties falling asleep. Additionally, their newfound sense of independence ("I do it myself!") may make bedtime routines more challenging. You might find that your toddler resists going to bed, wakes up during the night, and may even experience nightmares or night terrors.

2-Year Sleep Regression: This toddler sleep regression one often corresponds with the major life changes a 2 year old is going through, like potty training, transitioning from a crib to a toddler bed, or even welcoming a new sibling. Sleep issues like nighttime awakenings, resisting bedtime, and sleep anxiety are common symptoms.

Remember, not every baby will go through all these sleep regressions, and for some, they might be more mild or severe than for others. Sleep is a complex interplay of developmental, environmental, and sometimes medical factors. Sleep regressions are not caused by poor parenting or bad habits. 

What causes sleep regressions?

Sleep regressions are usually a sign of developmental changes and phases your baby or toddler is passing through. That said, the ways in which parents respond to these sleep challenges can shape your child’s sleep behaviors in the future - either fostering healthy sleep habits or unintentionally encouraging night awakenings. It is crucial not to blame yourself; rather, focus on strategies to support your baby during these phases. A sleep regression shouldn’t last more than a week, if it does, it’s best to consult a sleep coach on the team here at Tiny Transitions, to discuss your struggles, so you can get help sooner vs. later.

Which sleep regressions are the hardest?

The term "worst" can be subjective and vary from family to family based on a range of factors including parental tolerance for sleep deprivation, the baby's overall temperament, and other concurrent life stresses. However, some sleep regressions are often cited as particularly challenging.

How to help your baby (and yourself!) through the hardest sleep regressions

4-Month Sleep Regression

Why It's Considered Tough:

The 4-month sleep regression is often a parent's first experience with a major sleep upheaval, making it particularly hard. Babies' sleep cycles become more like adults', meaning they experience lighter sleep stages and wake up more easily. This regression also tends to be the first instance where previous "sleep crutches" (like rocking to sleep) might stop working.

How to Fix It:

Start Simple Sleep Training: Implement gentle methods to help your baby learn to fall asleep independently.

Consistent Bedtime Routine: Create a quiet, calming pre-sleep routine to signal that it's time to wind down.

Optimize Sleep Environment: Keep the room dark, cool, and consider using white noise.

18-Month Sleep Regression

Why It's Considered Tough:

This sleep regression often coincides with an explosion in mobility, vocabulary, and a budding sense of independence. These factors, combined with separation anxiety, can make bedtime and staying asleep a real challenge.

How to Fix It:

Set Boundaries: Be consistent with bedtime rules, even when your toddler tests them.

Offer Comfort: Provide a security object or lovey for emotional support.

Be Brief During Night Wakings: Reassure quickly and leave the room so that lingering doesn't become a new sleep crutch.

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

Identifying a sleep regression can be a bit tricky, especially for new parents who may not yet be familiar with their baby's sleep patterns or for those whose babies have naturally variable sleep habits. However, there are several telltale signs to look out for:

Signs of a Sleep Regression:

• Sudden Change in Sleep Patterns: If your baby was previously sleeping well but suddenly starts having difficulties, it might be a sleep regression. This can manifest as increased difficulty falling asleep, more frequent night wakings, or shortened nap times.

• Increased Fussiness: Many parents report that their baby becomes unusually fussy or cranky during a sleep regression. This can happen both during the day and at night.

• Changes in Appetite: Sometimes babies going through sleep regression will have changes in their eating habits, which could mean either an increase or decrease in appetite.

• Clinginess: Some babies become particularly clingy or anxious around their primary caregivers during a sleep regression. You might notice that your baby wants to be held more often and may exhibit signs of separation anxiety.

• Newfound Skills: If your baby is suddenly showing off a new skill like rolling over, crawling, or pulling up, it could disrupt their sleep and be a sign of a sleep regression. Babies often "practice" these new skills even when they should be sleeping.

• Resistance to Sleep Routine: If your baby starts to resist going down for naps or bedtime when they previously didn't, it might be a sleep regression.

• Increased Night Wakings: If your baby used to sleep for longer stretches but suddenly starts waking up more frequently during the night, that's a classic sign of a sleep regression.

• Restlessness During Sleep: Some babies during a regression period move around a lot during sleep, more than they usually would. This restlessness can wake them up and make it difficult for them to get back to sleep.

What is the best way to deal with sleep regression?

Dealing with sleep regression can be a challenging time for parents, but it's helpful to remember that sleep regressions are typically temporary and related to a change in your baby’s needs as he grows. Here are some strategies to help you manage:

• Stick to Routines: Maintain a consistent sleep schedule and bedtime routine, even if it seems like it's not working. The predictability of a routine can be comforting to babies.

• Pre-Sleep Ritual: Create a calming pre-sleep ritual that might include a warm bath, reading a book, or some soft lullabies. This can signal to your baby that it’s time to wind down.

• Dark and Cool Room: Babies sleep better in a room that is dark and slightly cool. Consider blackout curtains and adjusting the thermostat.

• White Noise: Many parents find that white noise helps to drown out other household or street noise.

• Limit Sleep Props: Try to avoid letting your baby become dependent on being rocked, fed, or held to sleep, as this can complicate things when you’re trying to teach them to fall back asleep independently.

• Brief Reassurance: It's okay to go into your baby's room to offer brief comfort, but try to avoid picking your baby up if it’s not necessary. The aim is to reassure your baby that you’re there, but also encourage self-soothing.

• Health Check: Make sure that your baby's sleep disruption isn’t due to illness, ear infection, or teething. Consult your pediatrician to rule out medical reasons for sleep disruption.

• Flexibility: While consistency is essential, be prepared to adapt your strategies as you learn more about your child's changing needs.

• Trial and Error: It’s often a process of trial and error to find out what works best for your child, and that's okay.

• Seek Help: Don’t be afraid to ask for help from someone, that’s what we are here for. Baby Sleep Coaches can assess and often see things you miss being in the thick of it.

If any of the above points resonate with you, then hiring a baby sleep coach could be a beneficial step for your family. Sleep coaches can offer personalized, one-on-one guidance and help develop a tailored sleep plan that works for your baby and your family dynamics. For sleep coaching and other new parent services be sure to visit Tot Squad and find more expert advice.

Further Reading

Baby Sleep and Travel: How To Maintain Baby’s Sleep Schedule

Stephen Hawkins, MD On The Science Behind Baby Sleep

Why Won’t My Baby Sleep? Common Reasons & Expert Tips to Help

7 of the Best Baby Sleep Products, According to Our Baby Gear Experts

Little One Not Sleeping? We Have Expert Advice To Help