Raising Littles

What Is A Split Night?

A split night occurs when your baby sleeps for a long stretch in the beginning of the night, but wakes for one long stretch in the middle of the night before falling back asleep for another stretch. Parents generally describe this as a middle of the night party, because their baby is wide awake, happy, and nothing gets them back to sleep.

It’s important to note that this can happen from time to time. However, if it’s become a pattern and happening consistently than there is probably something underlying happening.

What Causes A Split Night?

A split night largely stems from a separation between the circadian rhythm and sleep pressure. The circadian rhythm is the body’s internal clock. Whereas, sleep pressure builds as our wake time increases. When these two drives are aligned, your baby will build sleep pressure after their last nap and into the evening. They will go to sleep at their circadian linked bedtime, and “sleep through the night.” As sleep pressure dissipates into the morning, the circadian rhythm takes over and keeps your baby asleep until their regular wake time.

However, when split nights occur, the sleep pressure drive separates from the circadian rhythm. This means that your baby may sleep for 7 hours and wake up feeling ready for the day at 2am. During this wake time your baby will build up a bit more sleep pressure and sleep for a few more hours.

Generally, split nights occur due to unbalanced daytime sleep. This could be that daytime sleep duration is too high and/or bedtime is too early. However, they can also happen when naps are too short and bedtime is too early. For instance, if your baby is having short naps or not napping well, and you’re offering an early bedtime consistently for a few days and/or you’re letting your baby sleep in, a split night may develop. On the other hand, if your baby is getting an excessive amount of daytime sleep, they may not have enough sleep pressure built up to make it through the night. during developmental progressions.

How To Fix It

•You could try an earlier wake and leave the rest of the day as normal. This may allow your baby to get enough sleep and wake time. For instance, it’s easy to let your baby sleep in after a split night, but this might be perpetuating the split night. Waking your baby at their normal wake time or slightly earlier may be helpful.

•Babies can only have so much sleep in 24 hours. If your baby is napping too long or having too many naps, you may need to drop a nap or reduce the nap duration of some or all of the naps. This may mean you need to add in a short nap (<30 mins) at the end of the day to to compensate. The last nap should end allowing for a full wake window before bed or bedtime may need to be pushed back to allow for enough sleep pressure to build.

•If naps are working for you and you don’t want to make any changes, you could try pushing bedtime later in 15 minute increments until you’ve resolved the split night or got to a place where things are working for you. This may make for a late bedtime.

•If you want to leave bedtime at a certain time, you may need to cap the last nap before bed to be sure enough sleep pressure has built up. For example, if your baby has a 3 hour wake window and you want bedtime at 7, they need to be awake by 4.

•Another option is to shift bedtime later 15 mins every 3 nights until you’ve got bedtime to 8:30pm. If the split night has not resolved, trying waking baby 15 mins earlier every morning. When you have the split night resolved, you can start making bedtime earlier in 15 minute increments every 3 nights. Again, you may need to add a cat nap, extend a nap, and/or extended the mid-day wake window to compensate for the later bedtime and earlier wake.

•If your baby is overtired or has had a few days of rough sleep, you could try having a catch up sleep day. Get the sleep however you can for as long as you can and see what happens. If naps are short, you could try to extend the naps (e.g., rocking, laying with them) and/or offer an earlier bedtime (but not too early).

•If your split night is due to a developmental progression (e.g., your baby is working on a new skill), I don’t recommend making any big changes. I generally recommend waiting it out and giving your baby lots of time during the day to practice their skills.

Please note, resolving split nights takes time, patience, commitment, and experimentation. I generally recommend parents try one thing for 1-2 weeks before deciding whether or not it’s working and whether to try something new. Although, it can take longer to see results.