Crying isn't the goal of this sleep training method, but advocates say it's often an inevitable side effect as your baby adjusts to sleeping on his own. They say the short-term pain of a few tears is far outweighed by the long-term advantages: A child who goes to sleep easily and happily on his own, and parents who can count on a good night's rest.
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.
C.I.O. is the most famous sleep training technique, and the most controversial — although, despite its daunting name, it is safe and effective. In its simplest form, unmodified extinction, you place your infant down at bedtime, drowsy but awake, and then leave the room, without returning to check on or soothe your baby. This method will work quickly, but often produces prolonged periods of crying for a few nights, which can be difficult for parents to tolerate.
Some experts suggest techniques that are slightly different than these methods. Perhaps the best known is pediatrician Harvey Karp, author of The Happiest Baby on the Block. His method suggests a very specific routine involving the so-called five S's: swaddling, the side or stomach position (for calming your baby, not for sleeping), shushing, swinging, and sucking.
After going through your bedtime routine, put your baby in their crib, leave the room and wait a specific amount of time (say, a minute). Then go in and reassure your baby with words like “Mommy loves you” or some kind of touch, such as a rub or pat. McGinn says it’s preferable not to pick the baby up. Garden, on the other hand, reserves this method for babies seven months and older. (In her opinion, younger babies require a parental presence so they know they haven’t been abandoned, especially if they’ve worked themselves up into a frenzy.)
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.