A version of this technique called graduated extinction was popularized by Dr. Richard Ferber in his book “Solve Your Child’s Sleep Problems.” Here, parents check on their child at set intervals. Checks should be brief and to the point: Picking up your child, spending too much time hovering over the crib or otherwise offering more contact than a quick soothing word can be counterproductive. Some babies find these brief checks soothing and will go to sleep more quickly. Others will redouble their crying as soon as their parents leave the room. Parents need to make a judgement about whether or not checking in is helping their baby through this process. If you decide to use checks, I would recommend checking no more than every five minutes and resisting the temptation to check if your child seems to be calming down.
Thank you for your comment – I’m so glad to hear that the article was helpful for you! Generally we suggest trying for about an hour before giving up, but it can depend on the baby’s age and personality. We do have an article all about nap training that may help you here, as well: https://www.babysleepsite.com/baby-naps-2/nap-training-how-and-when/

I have a 5 month old girl who has been inconsolable when it’s has come to going to sleep, whether it be nap time or bedtime. Up until 6 weeks ago she was very good at self soothing, where I’d put her down drowsy/almost asleep, put on some soothing music and she’d toss and turn for a few minutes and fall asleep. Initially I thought it was the famous 4 month sleep regression but now it’s starting to get out of hand. Just to note, she used to sleep about 30-45 minutes and occasionally longer. She seemed happy and content when she woke so I assumed she had had enough rest, although I would’ve preferred longer naps. Also to note, She currently sleeps anything up to 8 hours at night and wakes for a feed around 3-5am.
Also on the far end of the cry it out spectrum is the Baby Wise approach by pediatrician Robert Bucknam and co-author Gary Ezzo. In their book On Becoming Baby Wise, they advise against feeding babies on demand around the clock and instead advocate a parent-led feeding, wake, and sleep schedule. Their method involves following a strict nap and sleep schedule and putting your baby down awake so she can learn to soothe herself to sleep. This means there will be some crying, especially at first, as your baby adjusts to your schedule.
Some of these experts think cry it out methods are not good for babies. Pediatrician and "attachment parenting" advocate William Sears devotes an entire chapter of The Baby Sleep Book to a critique of cry it out approaches. Sears, along with no tears advocates such as Elizabeth Pantley (author of The No-Cry Sleep Solution), believes that cry it out techniques can give your child negative associations with bedtime and sleep that could last a lifetime.
Raising a healthy sleeper starts with a consistent bedtime routine. You can start enforcing this when your baby is roughly six weeks old. At the same time every night, read a book together, sing songs, and feed your baby before putting him or her into the crib. It may also help to get your child up at the same time every morning and put him down for naps at regular times.

Most sleep coaches say the ideal time to start sleep training (or promote independent sleep, not necessarily using the cry-it-out method) is based on your baby’s development, but is usually somewhere between four and six months, when your baby hasn’t had much time to get used to nursing or rocking to sleep. At this stage, most babies are also developmentally ready to learn the skill of falling asleep on their own, explains Jennifer Garden, an occupational therapist who runs Sleepdreams in Vancouver. Around four months of age, some babies go through a sleep regression because their sleep cycles change and there are longer periods of lighter sleep per cycle. “It’s a great time to work on independent sleep skills,” says McGinn. Other babies’ slumber derails around this time because they are working on new skills, like moving around and rolling. Some parents choose to wait until things settle down before embarking on a sleep-training method, but you don’t have to, says McGinn.
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