Sleep Latency: the key to unlocking sleep secrets

So, what is sleep latency?

Simply, sleep onset latency refers to the time it takes to fall asleep.

Once your child’s needs have been met and the bedtime routine is completed, we are interested in the time it takes them to drift off to sleep. This can reveal lots of secrets about sleep, including how we can manage sleep to optimise it.

What does sleep latency tell us?

Sleep latency can reveal some interesting insights into how we can best support a child’s sleep by giving us clues about their levels of tiredness.

Sleep latency is closely related to our levels of tiredness so it can change day to day. However, because it is influenced by sleepiness, it is also impacted by how much of a sleep debt we have. This can make it a useful indicator to understanding if a child is sleep deprived or getting the right amount of sleep! If we identify that a child does have a sleep debt, we can work to try and get them out of it, and in turn, we will see a shift in their sleep latency.

The other reason sleep latency is useful is that we don’t always feel sleepy when we have a sleep debt. Often in children particularly, they can become more hyperactive and wired. Some people call this time the ‘witching hour’. what is likely happening is that cortisol levels spike to keep us alert, resulting in a surge of activity, which can often come up as dysregulation in little people.

Basically, sleep latency indicates if we are having sufficient quality sleep! As parents, these measures can be useful tools to help meeting your child’s sleep needs.

5 minutes or less:

Falling asleep really rapidly in less than 5 minutes can be an indication that a child is severely sleep-deprived. This rapid onset of sleep can be an indication there is a need for significantly more sleep especially if a child is often highly dysregulated or grouchy throughout the day. However, if your child has always seemed to fall asleep very quickly and is happy and healthy, this may be their norm and is nothing to worry about!

To help a child who is particularly tired, supporting them to sleep using soothing sensory tools like shushing, swaying and sucking can help to drift off to sleep easier at nap times during the day. The mission here would be to add more sleep to the end of naps or overnight sleep to build up the amount of sleep achieved in a 24-hour period. Contact naps may be useful here to support some additional sleep for your little one. Eventually, you might find a shift in their sleep latency or their sleep in 24 hours may reach the recommended thresholds (find out more about that here).

5 to 10 minutes:

Falling asleep quite quickly can be an indicator that more sleep during a 24-hour period would be useful for this little one.

10 to 15 minutes:

10 to 15 minutes is a manageable sleep onset latency and might not be anything to worry about. It may be your child’s optimum. You could have a go with adjusting the amount of sleep they have over a week or so, playing with adding sleep or increasing daily activity levels to see if this changes. This may well be your child’s sweet spot, but playing with sleep timings slightly may reveal some benefits to their mood and energy the following day. Experiment!

15 to 20 minutes:

Whilst leaning over the cot bars for a whole 15 minutes might feel like a lifetime, 15 to 20 minutes has been suggested to be the optimal time to fall asleep as it means the body can drift into a light sleep state slowly as opposed to ‘crashing’ into sleep which can cause sleep to be a little more jolty. A child who falls asleep too quickly might experience shorter sleep duration and more frequent wakes as they move through their sleep cycles in a funky way.

Over 25 minutes:

If a little one frequently takes 25 minutes or longer to fall asleep, it could indicate that some adjustments to their sleep timings need to be made. There are 2 core reasons we might want to change sleep timings if it is often taking this long: firstly, it can add a lot of stress when you are a tired parent trying hard to support your child to sleep, and it is taking a long time. This is the stress we simply don’t want on our plates! Secondly, long periods of being awake in their room might lead little ones to get frustrated and lead to more dysregulation before sleep, which again adds stress to both parties! If this persists for a long time, we can all get a little frustrated and begin to negatively associate bedtimes and sleep with tension and anxiety.

If this is the case for your family, I would recommend keeping a sleep diary! Take a look at how much sleep they are getting in a 24-hour period and see if they fall roughly around the recommended brackets. If they are achieving enough sleep, I would recommend moving bedtime a little later, perhaps by 15 minutes, to hopefully help them fall asleep within a good time. If they seem to be having more sleep than average, you could try capping their last nap of the day and keeping bedtime at the normal time.

Play around with it over a couple of weeks to see what works for you!

If issues persist, it might be worth checking in with your Doctor to explore any underlying causes of your sleep concerns.