4-month sleep regression: What it is and how to survive it

If you're a parent of a young infant, chances are you've heard about the dreaded 4-month sleep regression. Learn what this means for your baby and how you can help them out by transitioning through the phase as quickly as possible.

Sleep regressions happen when your baby’s sleep schedule shifts. During a sleep regression, your baby is much more likely to wake in the night and have difficulty going back to sleep. Sometimes babies struggle with sleep, but your baby’s inability to sleep isn't necessarily a sleep regression.

For babies that do show signs of regressions, it's important to understand why they’re going through these changes. If your baby experiences a sleep regression, it’s likely to happen around the 4-month mark, although every baby is different.

Why do sleep regressions happen?

Sleep regressions often happen due to your baby’s neurological development. Sleep regressions can also be due to your baby’s rolling, kicking, and turning movements whilst asleep, but this isn't at the heart of what causes them.

The brain changes that happen at this age can become quite overwhelming for them to process, so your baby’s sleep can change drastically. At 4 months, babies develop a more defined sleep cycle and start sleeping more like an adult than a newborn. Your baby has to cycle through sleep stages, and they begin to produce their own sleep hormone (melatonin). 

In the newborn stage, your baby is much more likely to be able to sleep at any time. Once they reach the 4-month mark, you might notice that sleeping isn’t as easy anymore, resulting in overtiredness and fussiness.

How do I know that it’s not a sleep regression?

Sometimes your baby can have trouble sleeping for other reasons. However, the difference is that these other issues don’t generally last more than a couple of days and are easier to handle. Some things that can affect your baby’s sleep are:

  • Periods of nap transitions (such as changing how often your baby naps)
  • Whether your baby is awake for longer wake times during the day, so they’re less tired at night
  • Sleep alterations due to travelling
  • Moving into a new house
  • A change in the parent’s sleep schedule
  • Separation anxiety
  • Teething
  • Growth spurts

If it’s not a sleep regression, your baby will likely settle down again in a few days. However, if your baby continues struggling to sleep, it may be a sleep regression.

What are the signs of a sleep regression?

The most common description by parents of a sleep regression is that their baby is sleeping well, and then, out of nowhere, their sleeping pattern changes dramatically. Other signs to look out for are:

  • An increase in night-waking
  • Increased crying and fussiness
  • Missed or shorter naps (catnapping)
  • Your baby is overtired when awake

How can my baby self soothe?

As mentioned before, your baby’s way of sleeping will change during a sleep regression. They may start catnapping more (a very light, short sleep) and be exhausted for bedtime because catnaps are the least refreshing type of nap for babies. 

It’s important to allow your baby to self soothe little by little from the first months of their life, as it can benefit their napping and night-time sleep later on. 

Self-soothing (or self-settling) means allowing your baby to develop the ability to fall asleep without the parents’ help. It’s something that any baby can do if everything is aligned correctly, such as their awake times, bedtime routines, and environment. 

Babies around this age are especially sensitive to light, and the slightest change in a room can trigger them to wake up. There are some other positive sleep associations you might want to include (even for naps), such as pacifiers and sleep sacks. 

As a parent, you may be used to reacting to every single sound or movement your baby makes and proceed to settle them immediately. However, when you immediately try to soothe your baby, you’re not giving your baby the chance to work on the new skill of self-soothing.

Self soothing doesn't mean leaving the baby to cry out. Instead, it has to be done little by little. In the beginning, self-soothing should involve more physical contact from the parents before changing to more vocal support. Eventually, your baby will be able to self-soothe independently. 

Final thoughts from Kami

Sleep regressions usually last between 2 to 4 weeks, and some parents might need some extra support and guidance during this time - this is completely fine. This is typically a very popular time to reach out to a sleep consultant. A consultant can provide medical advice and help promote healthy sleep habits for your baby.

Understanding what sleep regressions are and knowing what you can do to control them can help when your baby starts to fuss. Ultimately, you can’t manage every second of your baby’s sleep at this stage in their life, but you can be there for the journey and adapt if they’re having trouble.

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