SCIENCE

New Moms Live & Die By Wake Windows, But There’s No Proof They Work

If TikTok has you stressed about your baby’s sleep schedule, you aren’t alone.

When the TikTok algorithm started to serve me videos about wake windows, my son was 2 weeks old, and my husband had just gone back to the office. My newborn slept in weird spurts throughout the day (as newborns tend to do), and at night, he woke up every hour or two to eat. Family members mentioned he might have his days and nights confused, delicately implying I should be the one to set him straight.

Weeks stretched into months. My friends’ babies started sleeping in long stretches at night, and I wondered how I’d already managed to screw up our chances at the same. So there it was, my project for the last month of my lonely, unstructured maternity leave: fix my baby’s sleep. I did not know then that this would be impossible, and that every night for the first year of his life, no matter what I did, we would wake up. I only knew that my For You Page had delivered me a beautiful blonde sleep consultant who promised that wake windows were the answer. She was offering me the holy grail in the form of an easy-to-follow $10 PDF download.

The concept of the wake window is deceptively simple: It is the amount of time your baby should be awake before being laid down for a nap, a time period that gets longer with age, according to sleep consultants’ anecdotal experience. I did some Googling, and quickly discovered that wake windows were all over the place. You can find articles about the concept on major infant care brands’ websites, from Mustela to Love to Dream, a swaddle company. The Insta-famous Taking Cara Babies’ wake window guide is one of the most prominent Google search results on the topic, as is Dr. Harvey Karp’s explainer (he’s the Snoo guy).

Parents are clearly hungry for the content: Google inquiries about “baby wake windows” and “wake windows by age” have skyrocketed in the last three to four years. A Google Trends report shows that searches for “baby wake windows” started rising toward the end of 2020, a year in which balancing work and child care became an all-encompassing and deeply overwhelming project. As naps became rare and precious windows of uninterrupted work time, wake windows offered a system to get babies to sleep faster and more reliably. There is now an endless well of wake window content on TikTok and Instagram, created both by sleep consultants offering expert advice and moms sharing their POVs of a day following their baby’s age-appropriate nap schedule.

I decided not to spend $10 on the sleep consultant with the impeccable Utah barrel curls. True, she looked well rested and her hair bounced in time with her own young baby on her hip, but I had discovered a wealth of free options online. I screenshotted a schedule, downloaded a tracking app, and set about our new system. We would wake up at 8am, eat and “play” (as well as any 2-month-old could), and then, as prescribed, I’d lay my baby down after an hour and 15 minutes. He would sleep for one hour — no more and, hopefully, no less — and then we’d repeat that cycle, with some slight variations, four more times that day. In this format, wake windows were not a rough estimate of how long my baby should be awake, but a regimented schedule that fully occupied me for 13.5 hours a day until his schedule-sanctioned bedtime at 9:30.

Google inquiries about “baby wake windows” and “wake windows by age” have skyrocketed in the last three to four years.

By knowing your baby’s wake windows, you can, the thinking goes, accomplish two things: put your baby to bed before they become overtired, which should make it easier for them to fall asleep. And second, understanding wake windows should maximize their (and effectively, your) nighttime sleep. By allowing your baby the allotted amount of daytime sleep they need, the thinking goes, you can help them get the bulk of their sleep at nighttime. This, of course, is every new parent’s fantasy.

The idea of wake windows makes a certain kind of intuitive sense: Tiny babies have tiny sleep cycles, and those cycles lengthen as they develop until they eventually get all of their sleep in one big chunk at night. At the end of their wakefulness, babies usually display some subtle signs they’re ready to nod off, like staring off into space or avoiding your eye contact. But new parents can miss these obscure signs of sleepy baby, waiting instead for their little one to fuss or cry. They might inadvertently keep them awake too long by trying to soothe them with feeding, playing, or cuddles. If an overtired baby (in that dysregulated, chaotic state parents know all too well) has a harder time falling asleep, it stands to reason that knowing when your baby should be laid down is crucial. Wake windows pinpoint that sweet spot to lay your little one down so they can drift off easily, and that is immensely alluring.

A wake windows schedule offered both form and function — it put a scaffold back in my otherwise shapeless day, a little program to work while I did what felt like a lot of nothing on repeat: washing bottles, sanitizing pacis, laundering tiny clothes, wiping that little butt over and over again. But now my baby’s sleep habits completely took over what was left of my mental real estate. If he woke up for the day before his schedule estimated he would, I adjusted the timing of every nap for the rest of the day. If he didn’t fall asleep by his Nap No. 2 timestamp, or sleep as long as he “should,” I’d redo all the math again.

Research has taught us a lot about infant sleep ... but none of that is as appealingly specific as wake windows.

Each adjustment felt like a set back — even a failure — one I’d pay handsomely for in more lost sleep overnight. And God forbid we went to the doctor, or the store, or anywhere that day, because he’d fall asleep as soon as the car got rolling, disrupting his schedule again and ratcheting up my anxiety. It became a lot easier to just stay home, which only added to my feelings of isolation. Little did I know, though, I was not alone.

While wake windows seem to have gone viral in the last few years, the concept is decades old. It started with Kylee Money, a pediatric sleep consultant who has worked with more than 1,000 families over 23 years, and others like her in the early aughts, who spawned the industry of sleep consulting as we know it today. “People like me started coming forward and saying, ‘I have this really specific skill set with pediatric sleep. I happen to be super good at it. I may as well make a business out of it,’” says Money, founder of Parenting Made Joyful. “What we all noticed with our clients is there are certain awake periods that babies do really well with naturally, at different stages of development. If you were to put, let’s say a 4-month-old down too early, or keep them awake too long, their ability to self-soothe and fall asleep for naps, or have a good night’s sleep is severely affected.”

Sleep consultants base their recommendations on scientific research, Money says, but there have not been any studies investigating wake windows specifically. Dr. Craig Canapari, M.D., a board-certified pediatric sleep specialist and director of the Yale Pediatric Sleep Center, agrees. “Wake windows are not really a term used in the sleep medicine field,” says Canapari, author of It’s Never Too Late to Sleep Train, and co-host of The Sleep Edit podcast. Canapari says he has reviewed many wake window schedules available online. In all of them, the amounts of time babies should be awake for doesn’t appear to be based on “any scientific evidence,” he says.

Wake windows were not just a rough estimate of how long my baby should be awake, but a regimented schedule that fully occupied me for 13.5 hours a day until his schedule-sanctioned bedtime at 9:30.

Research has taught us a lot about infant sleep: that it’s essential to cognitive development and physical growth, that the amount of time babies nap for is highly variable from kid to kid, and that some children just don’t need as much sleep as others (a trait that tends to last their whole life through). But none of that is as appealingly specific as wake windows.

To be sure, anecdotal evidence isn’t nothing; it’s how child-rearing information was passed down for centuries prior to social media. “I’ve done this since 2001, with over 1,000 families, and these sleep windows work for 95% of my clients,” Money says. “If you talk to 20 other women in this industry, in this space, you will find that is something that works across the board. Regardless of the method that you’re using for sleep training, the fact that wake windows are important doesn’t shift.”

Like all sleep advice I tried to heed over the first year of my son’s life, wake windows did not seem to apply to him. Instead, they became one more anxiety-inducing metric we never seemed to meet, something I should be doing that I couldn’t. But maybe I wasn’t a failure, just part of the unlucky 5%. It’s not hard to find other moms on TikTok lamenting the stress wake windows caused them, and a growing body of sleep consultants also suggesting parents ignore the idea. They acknowledge that prescriptive, age-based wake windows can cause parents unnecessary anxiety, and urge them instead to focus on learning how much sleep their actual baby needs.

Wake windows are based on countless other babies, all of whom were not my baby.

Wake windows are not touted as evidence-based sleep strategies by most consultants and sleep coaches, but they don’t come with a “warning: anecdotal” label, either. And in an era of anxiety-fueled parenting, it’s a distinction that matters. It certainly would have mattered to me. In my fragile state, updating my app frantically and recalculating when to lay my baby down for his third nap, it would have been nice to know that tracking wake windows as a strategy for easier nap times or getting more sleep at night is not scientifically proven to work. I’d have known I didn’t have to follow them down to the minute, that I wasn’t to blame when my son didn’t adhere to them. They’re based on countless other babies, all of whom were not my baby.

Wake window guides offer precise predictions for parents in a time when we are desperate for concrete information. Take this seemingly simple question: When will my 9-month-old drop a nap? Research suggests most children transition to one nap per day between 6 and 18 months of age, Canapari says. If the evidence-based answer to an exhausted mom’s question is, “Oh, sometime in the next year,” of course a resource that narrows that timeframe considerably is welcome. For example, Taking Cara Babies states that most infants go from two naps to one between 13 and 18 months of age, a notably smaller range. Pediatric sleep coach Desiree Baird’s website says your baby should be at least 14 months old before the switch, which is the average age it should happen anyway, according to pediatric sleep consultant Nicole Johnson, “based on 15 years of experience.”

Having the insight of sleep consultants who have assessed thousands of babies’ sleep habits is certainly seductive, no matter how anecdotal. But this is also how harm can be done, Canapari points out, because the sleep consulting industry has no oversight, and a consultant can make any claims they want about the efficacy of their specific wake window schedules. Doctors, however, are bound to what has been proven and disproven by research. “As doctors we’re always kind of equivocating about stuff, like, ‘Well, this might be true in this situation, but it might not be true.’ If [following wake windows] gives you a structure to start with, I don’t think that’s a bad idea. It’s really unlikely to be harmful, but just recognize its limitations,” he says. (One can see how this kind of your-mileage-may-vary guidance isn’t what sells online courses.)

The wake windows holy grail: drowsy but awake, right between undertired and overtired.

I ask Canapari what parents who visit his practice ask him most often about wake windows. “I think the biggest one is, ‘What’s wrong with me? Why aren’t the wake windows working?’” he says. “It just doesn’t work for everybody. It’s not magic.”

Even a proponent of wake windows like Money acknowledges its limitations. Following templates online is setting yourself up to fail, she tells me. “I have a love-hate relationship with anything that you can look up online to help with sleep training, because what you’re finding is two pieces of a 100-piece puzzle,” she says. “Maybe those two pieces really make sense when you have the rest of the puzzle, but by themselves, they’re not actually going to impact your baby’s sleep. It’s like saying, ‘The screwdriver isn’t working,’ and you’re using the screwdriver with a nail.”

When she works with parents, Money spends time teaching them about sleep training before creating a personalized wake window schedule based on their baby’s specific habits and needs. Then her clients actually “have the tools” to use that schedule and make adjustments to it as needed, she explains. Sleep consultants can be extremely helpful to parents who want to know more about their child’s ideal nap times, Canapari says, because they can provide customized guidance and help you troubleshoot. It’s like the difference between internalizing therapy hacks you scroll past on social media versus going to actual therapy with a professional who can develop a rich understanding of your particular life, history, and needs right now.

Money acknowledges that a sleep consultant is not always in a family’s budget, and if your child is in day care, trying to follow wake windows is going to feel virtually impossible — because it is. “Frequently, day cares have their different classrooms on the wrong awake intervals, which drives me crazy, but I can’t fix that,” Money says.

Doing a little Googling about wake windows might be good if you’ve never thought much about your baby’s naps or wondered about how many they should take in a day, Canapari says, just to get a rough idea of what’s normal. Learning about them can also help you identify the subtle behaviors that indicate your baby is sleepy. But if wake windows are making you feel stressed, guilty, or they just don’t fit neatly into your life, there is no reason you have to follow them. “If it is causing more anxiety for parents to follow specific recommendations, then it’s best to take a step back and ‘listen’ to the baby. Most infants know their needs, but parents must be taught to identify them and respond accordingly,” says Dr. Nilong Vyas, M.D., a board-certified pediatrician, sleep consultant, and owner of Sleepless in Nola.

After my own year of trying (and failing) to get my kid to follow a regimented sleep schedule, I have come to embrace an entirely different philosophy: “We live in a cruel little chaotic universe. Nothing we do matters,” says Canapari with a laugh. “It’s the whole Donald Winnicott thing, right? The idea of the good enough parent: You love your kid, you’re nice to them. You do your best. They’re probably going to be fine. Do wake windows; don’t do wake windows. You won’t remember in five years whether or not you did them.”