This is a question I get almost daily when I talk to parents about their baby’s sleep. They want to know why their baby wakes up 30-45 minutes after bedtime. It is a common challenge that many parents face with their little ones.
When a baby wakes up 30-45 minutes after bedtime it is commonly called a false start.
What is a false start?
A false start is when a baby fell asleep at bedtime but was unable to connect their sleep cycles. This causes a wake up. This wake up happens most commonly between 30-45 minutes after falling asleep. This is typically the time they are transitioning into their next sleep cycle. Sometimes it can be up to 60 minutes before the false start happens.
Why false starts are challenging
Once a baby wakes up after their first sleep cycle, it can potentially be challenging to get back to sleep. The difficulty can depend on the reason that likely caused their wake up 30-45 minutes after bedtime. (More details on what causes these false starts below!) In all cases, the sleep pressure that was built up in your baby’s brain before they went to sleep has lowered, at least slightly, which can make it more challenging to get to sleep.
Sleep pressure is from our homeostatic sleep drive. This drive increases the need to sleep as we are awake and decreases the need to sleep as we sleep. So after some sleep, the need to sleep has decreased slightly creating a harder place to fall asleep from.
Why baby wakes up 30-45 minutes after bedtime
Overtiredness
Yes, when your baby is too tired can cause them to wake up more. Overtiredness is when your baby misses their ideal sleep window. Their body compensates for it with stimulating hormones like adrenaline and cortisol, which makes it harder to stay asleep. So one sleep cycle into bedtime when their sleep pressure has been lowered slightly, the over-tiredness helps push babies to wake up, often fussy and having a hard time getting back to sleep.
It often appears that your baby is fighting sleep. It likely feels to them that their body is working against them in going to sleep because of those stimulating hormones that are pumping through their blood stream.
Adjusting wake windows to avoid overtiredness is helpful in resolving false starts caused by overtiredness.

Baby isn’t tired enough at bedtime
The opposite of overtiredness, aka undertiredness can also cause your baby to wake up 30-45 minutes after bedtime. Being undertired is caused because not enough time passes between sleep periods to allow your baby to build up adequate sleep pressure before bedtime.
Again in this situation, allowing for age-appropriate wake windows helps resolve these false starts because your baby is tired but not too tired or not tired enough to fall asleep.
Bedtime too early
For young babies (younger than 4 months), as their circadian rhythms are starting to mature, a later bedtime often works best. So making bedtime too early can create a situation where baby treats their 7PM bedtime like a nap.
If you’ve got a really young baby and are experiencing a lot of false starts, you may need to move bedtime a little later to 8-10PM until your baby is around 4 months old. Around 4 months is when a between between 6:30-7:30 starts to work best, aligning with their circadian rhythm.
Baby was already asleep when put down in bed
Babies typically start to become more aware of their surroundings and what is going on to them and around them around 4 months. This is also the same time as the dreaded 4 month sleep regression (progression!) happens. The 4 month sleep regression leads to more light sleep as your baby’s sleep matures. This light sleep is also easier to wake up from. Your baby may come to the surface of sleep between sleep cycles, around 30-45 minutes after initially falling asleep, and realizes the situation and circumstances present when they went to sleep are not present anymore. Maybe they aren’t nursing any longer, don’t have the pacifier or bottle in their mouth and they are no longer being held or rocked by a parent or caregiver.
If your baby doesn’t know how to get themselves back to sleep, they will call out for help to get back to sleep as they awake between sleep cycles at the 30-45-minute mark after sleep onset. Working on independent sleep can help resolve these false starts. This is because then nothing has changed in your baby’s environment when they transition between sleep cycles so they are more easily able to stay asleep, especially assuming the factors causing false starts above are not present.
How independent sleep skills can help when baby wakes up 30-45 minutes after bedtime
As you can guess, since one of the common causes of false starts is putting your baby to bed already asleep, independent sleep can greatly help with false starts. When your baby knows how to fall asleep on their own they can more easily handle false start wake ups, because even if they are not in an ideal situation, they can still use their independent sleep skills to get themselves back to sleep.
There are lots of ways to tackle learning independent sleep and there is no one right way. We recommend that you find a strategy or philosophy that fits your family’s dynamics, comfort levels and parenting style. Consistency is key in helping your baby learn a new skill so finding a method you feel comfortable staying consistent with is key. (Don’t worry, if you don’t know where to start, we are here to help!)
Feeling unsure about what to do when your baby wakes up 30-45 minutes after bedtime?
Helping families overcome this common sleep challenge for babies is what my team and I do everyday. We help families develop step-by-step plans to get their little ones sleeping well. If you are struggling with false starts, babies or little ones not sleeping independently or other sleep challenges, reach out to me today to learn more about how we can help get you and your family sleeping better in just a few weeks!
Cheers to healthy, happy sleep,
Bonnie
*Updated February 2023*