Exhausted parents may be eager to get training underway—so how do you know when to start sleep training? “Most infants are ready for some sort of sleep training at 4 to 6 months,” says Lauren Kupersmith, MD, a clinical instructor at the department of pediatrics at NYU Langone Medical Center. “While some pediatricians adhere to the guidelines that infants are ready to be sleep trained when they achieve a particular weight, I feel it’s much more appropriate to wait until they are developmentally ready to self-soothe, at about 4 months old.”
Sleep experts who support the cry it out approach (as well as most pediatricians) disagree. They say it isn't traumatic for babies to cry alone for short periods of time with frequent check-ins by Mom or Dad – and the end result is a well-rested, happier child. They say no tears sleep strategies may cause babies to be overly dependent on comfort from a parent at bedtime, making it harder for them to learn to soothe themselves to sleep.
The age of your baby might determine what kind of sleep-training method you choose, though. You could try a gentle shush-pat technique with a five-month-old, but you’ll likely have to leave a one-year-old in the crib as they protest (cry or scream) about the new bedtime arrangement. Don’t attempt a formal sleep-training method before four months, until your baby is able to go longer in between feeds and their circadian rhythm starts to develop. (Many babies this age still feed in the night—contrary to popular thinking, sleep training isn’t synonymous with night weaning.) Dickinson says that many four-month-old babies are biologically able to go through the night without a feed, but that doesn’t mean you shouldn’t respond and feed them if other methods of calming them aren’t working. Since every situation is different, we recommend checking with your doctor before withholding your baby’s night-time feeds.