Sleep training is the process of teaching a baby to fall asleep independently, without being rocked, held, or nursed to sleep. The core idea is helping your baby develop the ability to self-soothe, both at bedtime and when they naturally wake during the night. It’s not one specific technique but a category of approaches that all share the same goal: your baby learns to drift off on their own when placed in the crib drowsy but awake.
What Sleep Training Is (and Isn’t)
Every baby wakes briefly between sleep cycles throughout the night. Adults do too, but we’ve learned to roll over and fall back asleep without fully waking. Babies who depend on rocking, feeding, or being held to fall asleep often can’t bridge those gaps on their own, so they cry for help each time. Sleep training teaches them to handle those transitions independently.
Sleep training is not the same as night weaning. Night weaning is about shifting your baby’s feeding schedule so they take in enough calories during the day and no longer need to eat overnight. You can sleep train a baby who still has one or two nighttime feeds. The two processes sometimes overlap, but they address different things.
Why Babies Are Ready Around 4 to 6 Months
The American Academy of Pediatrics notes that babies around 4 months old can begin learning to fall asleep on their own. By 6 months, it’s normal for a baby to wake during the night and resettle within a few minutes without help. This isn’t an arbitrary cutoff. Real changes are happening in your baby’s brain during this window.
In the first year, infants gradually shift from spending most of their sleep in active (REM) sleep to spending more time in quiet, deeper sleep. Research tracking babies from birth to 12 months found that quiet sleep increased significantly over that period, and the amount of quiet sleep a baby gets is considered a marker of neurological maturity. Babies with more mature sleep architecture are better able to self-soothe when they stir between cycles. Before about 4 months, most babies simply aren’t neurologically ready for that skill, which is why starting too early tends to backfire.
The Main Sleep Training Methods
All sleep training methods share the same destination but take different routes to get there. They generally fall along a spectrum from more parent involvement to less.
Unmodified Extinction (“Cry It Out”)
After a bedtime routine, you place your baby in the crib drowsy but awake and leave the room. You don’t return for crying, calling, or protesting until a set wake time in the morning, unless you believe your baby is sick, hurt, or in danger. This method has been used since the late 1950s. It’s the most direct approach and typically the fastest: infant sleep often improves within one week. It’s also the hardest emotionally for parents.
Graduated Extinction (the Ferber Method)
Instead of leaving entirely, you check on your baby at increasing intervals. You might wait 3 minutes before your first check-in, then 5 minutes, then 10. During check-ins, you briefly reassure your baby with your voice or a pat but don’t pick them up. The intervals get longer each night. This gives babies space to practice self-soothing while offering parents reassurance that they can still respond.
The Chair Method (Camping Out)
You sit in a chair next to the crib until your baby falls asleep. You don’t pick them up or interact much, just stay present. Every few nights, you move the chair farther from the crib: toward the door, outside the door, and eventually out of sight entirely. If your baby wakes and cries, you return to the chair’s current position and sit quietly until they settle. This method is gentler but typically takes longer because the changes are so gradual.
Pick Up, Put Down
When your baby fusses or cries, you pick them up and soothe them, but you put them back in the crib before they actually fall asleep in your arms. The idea is to offer comfort without becoming the thing that puts them to sleep. This is the most hands-on method and tends to require the most patience, as it can take many repetitions per night in the early days.
How Long It Takes
The more direct the method, the faster the results. Unmodified extinction and graduated extinction typically show clear improvement within a week. The chair method and pick up/put down can take two to three weeks or longer because the incremental steps are smaller. Most families see the biggest changes in the first three to five nights regardless of method, with the first night or two being the most difficult.
Consistency matters more than which method you choose. Switching approaches mid-course or responding inconsistently (sometimes going in, sometimes not) tends to extend the process because your baby can’t learn a predictable pattern.
The Effect on Parents
Sleep training is usually framed around the baby, but the impact on parents is significant. A study published in BMJ Open tracked mothers who used a sleep intervention and found striking changes in mental health within just a few weeks. At the start, 32.5% of mothers met criteria for at least mild depression. After the intervention, that number dropped to 5%. Stress levels fell from 48.8% to 20%, and anxiety decreased from 25% to 15%. Overall scores measuring depression, anxiety, and stress were cut roughly in half. Sleep deprivation is one of the strongest drivers of postpartum mood problems, so it makes sense that improving a baby’s sleep ripples outward.
Setting Up for Success
Whatever method you choose, a few things make the process smoother:
- Establish a bedtime routine first. A consistent sequence of events (bath, pajamas, book, song) signals to your baby that sleep is coming. This cue helps even before formal training begins.
- Put your baby down drowsy but awake. This is the single most repeated piece of guidance from pediatric sleep experts. If your baby falls asleep in your arms and wakes up in the crib, they’ll be startled and confused, not ready to self-soothe.
- Make sure daytime feeds are adequate. If your baby is still genuinely hungry at night, no amount of sleep training will override that need. Talk to your pediatrician about whether your baby is developmentally ready to go longer stretches without eating.
- Choose a calm stretch of time. Starting during travel, illness, or a major routine change adds variables that make it harder for everyone.
When to Hold Off
Babies younger than 4 months generally aren’t neurologically ready, and premature babies may need extra time based on their adjusted age. Babies with medical conditions, particularly breathing issues requiring a ventilator or continuous monitoring, need modified approaches. Illness, teething flare-ups, or developmental leaps (like learning to stand in the crib) can temporarily derail progress. In those cases, it’s fine to pause and restart once things stabilize.