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.
"My first cried it out, and all was well. My second cried it out but it took much longer until all was well. My third, if allowed to cry too long, literally freaked out. He threw himself around his crib and would rarely calm down and fall asleep. On the rare occasion that he fell asleep, he'd wake up within minutes screaming bloody murder. Letting him cry it out was clearly not working so I looked for other options. Find your child's groove. You'll be glad you did."
• Know there will be regressions. Teething, illness, vacation and routine shifts all can lead to poor sleep, and that’s all right, Vance says. “Often, you may have to go back to training for a day or two to get back on track, but you won’t lose ground. If your child has been trained to be a good sleeper, one week off schedule because of vacation won’t change that.”
There’s also no need to institute a regimented cry-it-out plan if what you’re currently doing is working for your family. But good sleep habits never hurt, and being able to fall asleep on one’s own is a necessary life skill. If you sleep-train at a time that’s developmentally appropriate for your baby and with the basic ingredients of healthy sleep in place, you can minimize the amount of crying your baby (and, let’s face it, you) will do.