“Cry-It-Out” Sleep Training: Is It Right for Your Baby?

Of the many sleep training tactics out there, the “cry-it-out” (CIO) method is one of the most infamous. Its proponents swear by it, claiming that you can see results within a few days, but does it really work, and is it good parenting?

Let’s break down how this controversial method works to help you decide if it’s the right choice for your family.

The “cry-it-out” (CIO) method—also known as controlled crying or extinction sleep training—involves putting your baby to bed while he’s still awake and drowsy, then allowing him to cry until he dozes off by himself. The goal is for him to learn how to self-soothe and fall asleep without your help, such as when you hold, rock, or feed him. 1

This approach can also teach him how to fall back asleep on his own when he wakes up during the night.

Don’t sleep-train a newborn. Sleep training won’t be effective if your baby is less than 3 months old and under 14 pounds. Before then, he’ll need frequent feedings, including during the night, and he won’t be able to properly distinguish between daytime and sleep time. 2

You can start sleep training once your baby is between 4 and 6 months of age. By this age, he’s old enough to learn how to self-soothe, and his sleep cycles should be developed enough for your baby to start sleeping through the night without feeding. 3

However, you should consult his pediatrician first before starting any sleep training method, especially if he was born prematurely, has any underlying health conditions, or isn’t gaining weight in line with his growth chart.

His doctor will also rule out any underlying medical issues that make him cry, such as an ear infection or acid reflux.

The success of this sleep technique depends on how consistent you are. Here’s a general outline of the steps you’ll take with the CIO method:

1. Establish a bedtime routine

First things first, make a consistent, calming bedtime routine to let your baby know that it’s time to get some shut-eyes.

Try a warm (not hot) bath. You can even read him a story or sing lullabies, since he’ll find your voice soothing. 4 Make sure that he doesn’t have any loose bedding, pillows, or stuffed animals in his crib that could lead to accidental suffocation. 5

You can keep track of your schedule in a journal or baby tracker app for easy reference and reminders.

2. Put your baby to bed when he’s drowsy but awake

After your routine (and a few cuddles and kisses), he might show signs of being sleepy, like yawning, crying, eye-rubbing, or getting fussy. Place him in his crib before he’s fully asleep so he can learn how to settle by himself.

If you wait too long, you’ll run the risk of your baby getting overtired, and he’ll be much harder to get down for the night.

3. Say goodnight and leave the room

Kiss him goodnight and leave the room. If he’s sharing a room with you, that’s fine, but if so, you might want to create a visual barrier between your beds with a divider. A curtain or sheet hanging from the ceiling works, too, as long as you quickly get to him in case of an emergency.

Resist the urge to give in even when he cries, although it’s probably going to be hard. The faster he learns to self-soothe, the faster the both of you will be able to get some sleep.

4. Be consistent

Stick to whatever routine you choose and avoid making changes mid-way through the process. You need to be able to commit to the training, so pick a time to start CIO when you’re relatively stress-free—not during periods of travel, illness, or major life changes.

You can try out different variations of the CIO method, although the core principle remains the same—allowing your baby to cry until he falls asleep.

One similar popular technique is the Ferber method. With this method, you’ll put your baby to bed and leave the room, but can go to check in on him at gradually increasing intervals. This means that on the first day, you may let him cry for five minutes before checking on him. On the second day, you can check in on him after 10 minutes, 15 on the third day, and so on.

When you do go to check in on him, don’t pick him up. A simple but soothing back rub or simply talking to him should be more than enough. 6

You could also experiment with how long you let him cry before intervening, such as waiting 15–20 minutes.

No matter how you choose to sleep-train your baby, know that there’s no single “best” approach. Some parents prefer the directness of extinction, while others find the graduated approach of the Ferber method more bearable. What you should do depends on what you’re comfortable with. 7

Normally, the unmodified CIO method works faster than other sleep training techniques. He should learn to fall asleep by himself within the first three to four days. Using the gentler Ferber method might take 7–10 days instead. 2 8

There’s nothing wrong with stopping and trying again later if you don’t see results. Talk to his pediatrician if you’re worried, and consider other sleep training techniques.

Alternative sleep training methods

If you don’t see results in that timeline—or if you’re just feeling uncomfortable about leaving your baby crying for too long—try some other popular options: 1

• The chair method: This gentler approach involves sitting in a chair next to your baby’s crib and gradually moving the chair further away each night until you’re out of the room (or out of sight).
• Fading method: Use whatever methods you normally would to get your baby ready for bed (e.g., rocking, soothing, or singing), but gradually spend less time doing them until you “fade” them out. Essentially, this method lessens the time you spend with your baby and encourages him to fall asleep by himself.
• Respectful sleep training: This is an adjustment you can make to the other methods that allows you to pick up your baby to comfort him and then put him back in his crib whenever he stops being fussy. The idea is still to phase your own presence out, but in a less rigid way.

If you opt for these alternative methods, your baby may take up to four weeks to settle into independent sleep.

Note that even if any of these sleep training techniques are successful, he may experience sleep regression at different points of his growth, which means there’ll be temporary periods where he has difficulty sleeping even if there were none before.

As mentioned, you need to be consistent. The CIO method requires several nights—or even longer—of trial and error for it to work.

Remember to keep everyone in the loop about your sleep training plans. You don’t want to have your partner, family or friends swooping in to comfort your baby while you’re trying to teach him how to fall asleep by himself. This might affect any progress you’ve made so far.

With all of that said, don’t leave your baby crying for hours unsupervised. While you can step out of the room, safety is still a priority. Use a baby monitor to keep an eye on him in case there’s a true emergency (or if he just doesn’t stop crying, which could mean he’s actually uncomfortable, not just fussy).

While the CIO method can help you and your baby sleep more, it isn’t without controversy.

Emotional distress

As a parent, you want to nurture your baby. Listening to him cry without intervening can feel like the worst thing ever and may leave you feeling guilty, anxious, or doubting yourself. The first few nights of CIO can be especially difficult. Prepare yourself emotionally and mentally.

The good news is that you shouldn’t worry too much about hurting your baby’s feelings—contrary to what you might think, sleep training won’t damage your bond with him or make him distrust you. However, even though it’s temporary, it can certainly be unpleasant enough in the moment.

Effectiveness

While CIO can be effective, it might not suit all babies. If yours tends to be calm and adaptable, he might adjust fairly quickly to a consistent bedtime routine and the idea of self-soothing, but if he’s sensitive or easily overstimulated, sleep training him might require a gentler, slower approach. He might take longer to adjust and will need more reassurance during the process.

This doesn’t mean he’s not capable of learning to sleep independently—he just might need more time and patience to get there.

You know your baby’s temperament better than anyone. Pay attention to how he reacts to different approaches so you can make the process less stressful for both of you and make him feel secure.

Health concerns

Some critics argue that leaving your child to cry increases will make him more stressed and elevate his cortisol levels, potentially impacting his emotional and behavioral development.

However, short-term sleep training shouldn’t have any lasting negative effects. Remember to establish a comforting bedtime routine and to check on your baby if he’s crying for hours at a time. 9 10

It’s worth noting that some babies get so worked up that they vomit, although this is rare. If it happens, stop the training, comfort him, and consult his pediatrician.

Some parents use the CIO method for naps. If you want to do that, you can, but it’s important to approach this with care.

Always be mindful of how he’s responding and make sure his crying doesn’t become too intense. If he’s used to being rocked to sleep or nursed at naptime, it may take a while for him to adjust to falling asleep independently.

There’s no one-size-fits-all approach to sleep training. If you find that the cry-it-out method works for you and your baby, go for it, but if you’d rather take a gentler approach, that’s fine, too.

What’s most important is to find a method that works for your family and ensures both you and your baby get the sleep you need. If you’re ever unsure, don’t be shy about reaching out to your baby’s doctor.