Is your baby wide-awake (but happy) for hours in the middle of the night?

It’s 2 a.m. and my six-month-old daughter is wide awake. She isn’t crying, and she isn’t hungry—she's perfectly happy to be hanging out, as long as I don’t leave her alone. But we are on hour two of this wide-awake, ready-to-party mode, and it’s the middle of the night. No matter how much I shush, pat, hum or feed her, her little eyeballs are peeled open.

It’s not until we pass the two-hour mark that she begins to yawn and rub her eyes, and I know she’ll finally go back to sleep. 

Like usual, she’d gone down easily at the beginning of the night. It’s become a pattern for us: After our standard evening bedtime routine and sleep training, I settled into the couch for some kid-free time to relax and re-watch Downton Abbey. But a few hours after I put myself to bed, my daughter inevitably wakes up.

She’s happy as can be and ready to play, inspecting the lamb sewn on her sleep sack, even laughing as the cat walks by her crib. 

After some time speaking with sleep consultants, I now know there’s a term for this particular baby sleep phenomenon: split nights. And for many people, this is what's keeping baby awake at night.

What are split nights?

Split nights, segmented sleep, bifurcated sleep—no matter what you call it, it’s frustrating and exhausting to put your baby to bed, only to have them wake in the wee hours of the morning and stay awake for an hour or more. 

Sometimes a baby simply has an off night—we all do! Maybe it’s digestive discomfort, constipation or a growth spurt. Perhaps they’re working on a new skill. Underlying issues can cause nighttime wakings for up to two weeks. But if this has been going on for more than two weeks, and it’s happening at least five nights a week, sleep experts agree that it’s probably a split nights issue. 

What causes split nights? 

Two biological aspects drive sleep: circadian rhythm (our natural tendency to sleep when it’s dark, spurred by the release of melatonin hormones) and sleep pressure (which builds while we are awake). Normally, pressure builds during the day, your baby goes off to dreamland, and when the pressure subsides, circadian rhythm and melatonin take over. A split night results when these two drivers stop working in sync.

Most often, split nights have to do with daytime sleep—meaning, how much your baby is napping during the day.

“We hear about these sleep totals, say 14 hours in 24 hours, so parents tend to focus on long naps,” says Lauren Heffernan, a Toronto-based certified pediatric sleep specialist with Isla Grace Sleep. But this can actually result in too much daytime sleep. If you have five hours total of naps during the day, she explains, then you’re basically deducting those five hours off their nighttime sleep.

With only nine hours of sleep left, they wake up partway through the night feeling refreshed, and it takes time for their sleep pressure to build again.

Another big reason for a split night is a too-early bedtime. On a bad nap day, you might move bedtime up to be earlier, sure. Doing this once in a while is great—but when it becomes a pattern, it too can result in split nights, since your baby is spending more time in bed than they need, explains Amanda Jewson, a sleep consultant in Stratford, Ontario with Baby’s Best Sleep.

“Every child has a total amount of sleep in them, and we have to aim for prime sleep pressure all the time. It becomes a mathematical equation.”

How do I fix my baby’s split nights?

You need to adjust daytime sleep totals and your baby’s bedtime. The Canadian Paediatric Society recommends 12 to 16 hours of sleep in a 24-hour period for babies four to 12 months and 11 to 14 hours of total sleep for toddlers. In the case of split nights caused by too much daytime sleep, you’ll have to shorten each nap slightly by waking your baby before they’d normally rouse and extending or stretching the time before the next nap.

Even a seemingly short nap of 30 to 45 minutes can be very restful, says Heffernan.

Of course, each baby is different and you may need to experiment with nap lengths and fiddle with your wake windows a few times before you find a schedule that allows your baby to build up sufficient pressure to stay asleep all night. This may also be achieved by dropping a nap altogether (depending on how old your baby is).

If you’ve been doing a fairly early bedtime, play with the nap schedule to transition to a consistently later bedtime. However, Jewson warns, you need to “avoid over-tiredness and under-tiredness, because both are just as deadly.”

You don’t want your baby to be so tired that they’re fussy, but they still need enough awake time in their day to prevent those middle-of-the-night crib parties. 

How common are split nights?

“I see it at all ages,” says Jewson—not just young infants. Before four months, newborn sleep split nights are totally normal. But from five months right through to toddlerhood, split nights are a possibility. “Even two-year-olds can experience 20 to 30 minutes of wakefulness and need support to get back to sleep,” says Heffernan of differing sleep cycles.

Can I just wait it out? 

If your little one is an independent sleeper, they may stay awake happily on their own in their crib or kids mattress, while sleep pressure builds up. “Definitely check in on them, but if they’re happy and safe, it’s OK to let them hang out in their baby crib,” says Jewson. Other babies (like my daughter) get distraught if left alone.

If they’re upset, create a connection point to help calm them, such as a soothing song or a long hug. If this is happening a few nights a week for only a week or two, it’s OK to just wait it out. Eventually, solid night sleep will find a way.

For some kids, nighttime is just too much separation. You can try to make their environment smell like you by placing a piece of your clothing near their crib or dabbing breast milk on their skin. Heffernan recommends making sure you and your baby have plenty of one-on-one time in the evening, if possible.

“Sometimes, you’re running around the house all day, they feel disconnected, and they see nighttime as a way to connect—this is especially true for toddlers,” she says.

Older toddlers may do well with an OK-to-wake toddler alarm clock that signals when it's time to stay in bed and when it's time to move around. These help regulate sleep patterns and offer positive cues to little ones even before they can tell time.

Can anything else cause night wakings?

Always address underlying issues as well. But sometimes a feed or a middle-of-the-night diaper change can actually wake your baby up even more, extending the split night. Of course, if they truly need a new diaper or are hungry, that’s a different story. But you should consider all options to help them fall asleep and stay asleep more than 1-3 hours at a clip.

Is your baby gassy from a new food? Are they getting enough milk? Are they experiencing reflux? Are they getting enough activity? This last one is a common cause for extended night wakings.

“During sleep, their brain is processing so much information, so if they wake, they might want to practice new skills, like rolling, sitting up or even chatting,” explains Jewson. Give your baby plenty of floor and tummy time to practice physical skills freely during the day.

“A lot of the time, your baby is in a container—a Bumbo, a high chair, an Exersaucer—and the crib is the only open space they have to practice rolling, crawling, sitting and pulling up,” Heffernan adds.

Playing with nap times, wake windows and achieving a later (but consistent) bedtime should do the trick. If it doesn’t, Jewson recommends contacting your family healthcare provider to rule out physiological issues, such as sleep apnea.

If you feel like you’ve done everything, calling a sleep consultant might be a good idea—doing the math with all these schedule adjustments can break your brain, especially if you’ve been up half the night.

How to deal with split nights

• Set up a healthy sleep environment for your baby. This includes a crib, bed or co-sleeping situation.
• Try a baby sound machine that makes gentle white noise. We like the affordable MyBaby white noise machine.
• Gradually decrease daytime naps or lessen the duration.
• Find soothing cues they can rely on.