What is a sleep regression?
There has been a great deal of talk about “sleep regressions.” What is a sleep regression? A sleep regression is reported to occur when a baby who was sleeping well (or relatively well) all of a sudden has a sleep issue, whether that issue is falling asleep at bedtime or waking frequently during the night. According to the cultural commentary that focuses on sleep regressions, they can occur multiple times in the first year of life (and beyond), whether at 4 months, at 8, 9, or 10 months, 12 months, or 18 months.
What do the data say?
A look at the data of sleep in young children, however, does not support a set time or month when sleep becomes problematic. The data simply do not show that there are specific months when all of a sudden a sleep problem develops. Instead, sleep is always changing and your baby will likely hit a bump in the sleep road at some point in the first year. This is totally normal.
To illustrate, a look at over 3,500 babies shows that the same percent of parents report sleep problems at every month across the first year of a baby’s life. For example, 32% of mothers report a sleep problem at 3 months of age, 25% at 4 months, and 30% at 5 months. These figures are consistently in that range for older infants as well. Similarly, mothers report just about the same number of night wakings, on average, at each month of age across the first year of life (1.7 wakings per night at 3 months, 1.6 at 4 months, 1.5 at 5 months, etc.). Note that these are average night wakings, not that a baby literally wakes up 1 and ½ times during a night. So, those sleep changes that are experience at different times across the first year are totally normal for a baby.
Say it with me, “sleep progression!”
Instead of thinking of a “sleep regression” when your baby’s sleep changes, realize that sleep is always evolving and sleep develops as your baby develops. So, consider thinking of it as a “sleep progression,” and potentially a sign of healthy development. There are many reasons why your baby may suddenly start having a hard time falling asleep or waking more often at night. She may be sick. She may have just learned to roll over, pull to stand, or crawl. All of these things are much more fun to practice than going to sleep, and they may interfere with falling asleep. Research even shows, for instance, that sometimes sleep becomes problematic right before a major developmental change.
It may also be that she is becoming more aware of the world. For example, at 3 to 6 months of age, sleep habits are becoming engrained. Babies are also beginning to develop sleep onset associations, or cues, objects, and/or people in their environments that help set the stage for sleep and – out of habit – sometimes become required for a baby to be able to fall asleep. Again, a sign of healthy cognitive development. Around the same time, babies also come to understand that objects exist even when they are out of sight, referred to as object permanence. This means that when you step out of the room at bedtime, she may fuss or cry since she has a better understanding that although you are out of sight (that is, you left the room), you still exist (you haven’t disappeared into thin air). Before developing object permanence, your baby likely has an out-of-sight, out-of-mind mentality. So, a bit of protesting at bedtime is completely normal and a sign of healthy development.
So, what should you do if your child’s sleep suddenly changes?
The first thing is to be sure that your child is not sick or having any medical issues, such as an ear infection or reflux. The second thing to understand is that you do have some control over your baby’s behavior and it is not something that you just need to live with. Third, stick with what you have always done. Be careful not to make changes to what you have always done or else you may end up heading down a path of developing habits that you may not want to continue (such as starting to rock your baby to sleep every night if you hadn’t before). And finally, consider making changes if things do not get back on track after 1 to 2 weeks. For example, if your baby fed to sleep at bedtime but always slept through the night but now wakes during the night, it may be time to start shifting to helping your baby self-soothe to sleep at bedtime or doing a bit of sleep training during the night. For more information, check out our section dedicated to sleep training.