Sleep Training: What Is the Perfect Age?

When is it too early or too late to sleep train your baby? (Photo: Getty Images)

Sleep training is a hot-button issue with many schools of thought and the most recent — covered by the New York Times in an article called “Sleep Training at 8 Weeks: ‘Do You Have the Guts?’” — stirred even more controversy. In the story, a national pediatric practice encouraged parents to teach their babies to sleep through the night starting at the age of 2 months. The topic generated loads of backlash with many calling the practice “disgusting” and a cause of “psychological harm.”

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The method sounds extreme but when it comes to sleep training, there isn’t a hard-and-fast rule about when to start, since all babies are unique. Most infants naturally start sleeping through the night — defined by five hours or more — at 2 to 3 months old, according to research published in the journal Pediatrics. The researchers also found that at 5 months old, 50 percent of babies sleep around the same length of time as their parents, from about 10 p.m. to 6 a.m.

If you want to sleep train, it’s generally wise to start when your infant is between the ages of 3 and 6 months old — with 6 months being the minimum age for parents who want to attempt a modified “crying it out” method.

“Around 3 months of age, infants acquire the ability to soothe themselves to sleep,” Judith Owens, MD, director of sleep medicine at Boston Children’s Hospital, tells Yahoo Parenting. “Prior to that, their sleep patterns are based largely on feeding schedules, and from a developmental standpoint, there’s not a lot parents can do to modify that.”

She adds, “After 6 months, healthy, full-term infants don’t need to eat during the middle of the night. They can go most of the night without waking up to feed.”

Just note that some babies (even the best sleepers) experience sleep regression at 4 months old so training then can be complicated. "Around 3 to 4 months old, their bodies start secreting their own melatonin — one of the hormones that regulates their circadian rhythm, or their internal clock,” Kim West, author of “Good Night, Sleep Tight,” tells Yahoo Parenting. “Wakings become more distinct during the night so they really have to work on putting themselves to sleep. Before that, we’re their external clocks. If you have a baby who has hard time at that 4-month regression, wait about two and a half weeks before you start sleep coaching.”

Another challenge some parents face is sleep training while sharing a bedroom with their infant. Both West and Owens say it can be done and recommend using a screen or hanging a curtain from the ceiling (that’s not too close to your baby so he can’t pull it down) to create a makeshift wall. This will help keep your infant from spotting you during night wakings and make him more likely to self-soothe. “Also, get a white noise machine so your baby can’t hear you setting your alarm, brushing your teeth, or talking to your partner,” suggests West.

Whichever sleep training method you choose, the best way to help your baby learn to self-soothe is to put him down while he is drowsy but still awake. That way, he won’t fall fully asleep secure in your presence but wake up panicked when you’re gone. And try to avoid having your baby require your breast or a bottle to fall asleep. If that seems difficult, you could try scheduling his last feeding of the day at 30 minutes before bedtime, suggests What to Expect.

“If they learn [to self-soothe] at bedtime, they can put themselves back to sleep for the partial arousals at night,” says West. Note: This advice is not to be confused with following a consistent and recommended bedtime routine in which you bathe and rock or cuddle with your baby until he’s sleepy but not slumbering.

Also, West points out one mistake some parents make while sleep training: Trying to keep a baby awake during the day, thinking it will help her sleep longer at night. “Becoming overtired makes our bodies secret cortisol, which is a stimulating hormone,” says West. “Your child then has a harder time going to sleep and staying asleep. You really want them to be well-napped before we start sleep training.”

And finally, if you haven’t introduced sleep training, don’t worry that your infant is too dependent on your presence to begin — Owens points out that separation anxiety usually starts at 12 months and peaks at 18 months old.

Above all, follow a sleep training method that feels right for you and your baby’s disposition. “It’s important that you pick a sleep coaching method that aligns with your philosophies and your child’s temperament and you do it consistently,” says West. “If you’re not seeing any progress, you might want to rule out underlying medical conditions. Or the sleep training method can be the wrong match [for your baby].”

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