Most experts recommend starting when your baby is between 4 and 6 months old. By about 4 months, babies have typically started to develop a regular sleep-wake cycle and dropped most of their night feedings. These are signs they may be ready to start sleep training. Many babies this age are also developmentally able to sleep for long stretches at night.
Hogg agrees with Sears that sleep associations should be positive but disagrees with his techniques. She cautions against letting your baby depend on "props" such as nursing, patting, and rocking to get to sleep. Instead, Hogg's approach calls for going to your baby when he cries, picking him up, and putting him back down as many times as necessary.
Sleep training is a loaded phrase, and one that is often used synonymously with letting your baby self-soothe, or “cry it out,” but that’s not the whole picture, says Alanna McGinn, a certified sleep consultant and the founder of Good Night Sleep Site. “It’s more about being able to teach your baby that they are capable of falling asleep independently,” she says. You want your baby to be able to nod off on their own—ideally without nursing, rocking or using a pacifier—because whatever tools they use to fall asleep at bedtime are the same things they’re going to wake up looking for during the night. Yes, this can feel unloving and even downright cruel. You’ll find experts on both sides of the issue: Breastfeeding advocates say it’s normal for babies of all ages to wake up multiple times to nurse, and even the sleep coaches interviewed for this article disagree with how much crying and distress are acceptable.