The "Happiest Baby" method: How the 5 S's help babies sleep (2024)

There's no sweeter sight than a sleeping baby, but getting your baby to sleep can turn into a daily struggle.

If you're a sleep-deprived new parent looking for help, you might want to try pediatrician Harvey Karp's method for soothing crying or fussy infants and getting them to sleep. At the heart of his method are the five S's: swaddle, side or stomach position, shush, swing, and suck.

The "Happiest Baby" method

Karp says the best way to calm your newborn and get them to sleep is by re-creating the noises, movement, and snug environment of the womb. The "five S's" baby sleep strategy outlined in his book, The Happiest Baby on the Block, is designed to do just that.

Many experts, including Karp, describe the first few months after birth as the "fourth trimester." Babies are out of the womb, but they're not quite ready for our world. Human babies need special care because they're immature at birth compared to the babies of most other mammals. (One example: A newborn horse can walk, while humans take months to get mobile.)

Many new parents may assume that newborns need calm and quiet, but the place from which they've just emerged is quite active and noisy. Babies in utero are rocked and swayed. They're bombarded with the whooshing and gurgling sounds of their mother's body and cradled by the walls of their "room."

So it's no wonder that they may feel insecure and unhappy when lying alone in a quiet nursery, their arms and legs loose and flailing. Creating an environment similar to the womb can comfort your newborn and help them sleep better – enter the five S's.

The five S's of baby sleep

While Karp recommends doing all five S's and taking care to do each of them exactly right, every baby is different. You don't need to follow all five S's if your baby doesn't need them. Some babies need only swaddling and being held on their side or stomach, for example. Experiment and see what works for your little one.

Karp's method is aimed at babies during their first four months of life. Once your baby is 4 months old, they're out of the newborn phase and their sleep and comfort needs are different.

Swaddling

Swaddling soothes babies by providing the secure feeling they enjoyed before birth. It also keeps your baby's arms from flailing and prevents startling, which can start the cycle of fussing and crying all over again.

Swaddling isn't hard, but it's important to get the technique right so the swaddle is safe and effective. You can use a thin blanket (here's a video on how to swaddle with a blanket), or you can buy swaddles with Velcro that make it easy and fast to wrap your little one up.

The idea is to wrap babies snugly so they won't try to wiggle out of the swaddle, but leave enough room at the bottom of the blanket for them to bend their legs up and out from their body. Do swaddle your baby for naps, for the night, and when they're crying. Don't swaddle when they're awake and happy.

It's time to stop swaddling your baby once they show signs of rolling over. This usually happens around 3 or 4 months, but can be as early as 2 months.

Learn more about the benefits of swaddling your baby.

Side or stomach position

Now that you've swaddled your baby, you can begin to calm your crying or fussy baby by putting them on their side or stomach while you hold them.

To reduce the risk of sudden infant death syndrome (SIDS), it's extremely important to put your baby to sleep on their back. But because newborns feel more secure and content on their side or tummy, those are great positions for soothing (not sleeping).

Hold your fussing or crying baby in a side or tummy-down position in your arms, on your lap, or over your shoulder. Use this "S" only for soothing your infant. Never put them on their side or stomach when they're asleep. If they fall asleep, put them down on their back.

Shushing

Shushing is a sound that calms and comforts your baby, helps stop crying and fussing, and helps them go to sleep and stay asleep.

Newborns don't need silence. In fact, having just spent months in utero – where Mom's blood flow makes a shushing sound louder than a vacuum cleaner – they sleep better in a noisy environment. (They're also happier, and better able to calm down.).

At its simplest, you apply the "shush" step by loudly saying "shhh" into your swaddled baby's ear as you hold them on their side or tummy. Put your lips right next to your baby's ear and "shhh" loudly (usually while gently jiggling them – see below).

Shush as loudly as your baby is crying. As they calm down, lower the volume of your shushing to match.

You can also use a white noise machine while your baby sleeps. Some sounds are much more effective than others. Karp says that fans, sound machines, and recordings of ocean waves may not work, and recommends sounds that are more low and "rumbly" (like the sounds in the womb). You can experiment and see what helps your baby.

Play the sounds as loud as your baby is crying to calm them down. To accompany sleep, play them as loud as a shower.

Swinging

A baby swing might be your first thought, but that's not what "swing" means in this case. Instead, it refers to jiggling your swaddled baby using very small, rapid movements.

In utero your baby was often rocked, jiggled, or otherwise in motion. That makes this "S" familiar and comforting. Do this while shushing (or playing white noise to) your swaddled baby in a side or stomach position.

Be sure to support your newborn's head and gently jiggle – do not shake – your baby. Karp describes it as more of a "shiver" than a shake, moving back and forth no more than an inch in any direction.

In Karp's opinion, other types of movement (being rocked in a rocking chair, swung in a baby swing, or carried in a sling, for example) are useful for calm babies, but this gentle jiggling is more effective for a wailing baby.

Sucking

This simply means giving your baby a pacifier or thumb to suck on. Some babies love to suck and find great comfort in it. If your baby is in that camp, sucking may help them relax and calm down.

Give your swaddled baby a pacifier or your thumb if they're upset and seem to want to suck. In combination with being held on their side or tummy, being soothed with loud shushing or white noise, and being gently jiggled, sucking may do the trick to calm your baby.

Pacifiers can also reduce the risk of SIDS, and it's okay to let your baby keep the pacifier while they sleep. Some experts do say to wait to give your baby a pacifier until after breastfeeding is established, since sucking on a pacifier feels different than sucking on a breast, and the pacifier could interfere with early feeding.

Learn more:

• Newborn sleep guide
• What to do when your baby cries for no reason
• Is it normal for your baby to cry all the time?