At nine months old, your baby’s brain and body are going through a perfect storm of developmental changes that frequently disrupt sleep. This is one of the most common ages for sleep to fall apart, even in babies who were previously sleeping well. The good news: it’s almost always temporary, driven by predictable milestones, and there are concrete things you can do about it.
The 9-Month Sleep Regression Is Real
Around nine months, babies are learning to crawl, scoot, pull to stand, and sit independently. These are massive neurological achievements, and they come with a cost: your baby’s brain is so busy processing new skills that sleep takes a hit. Many babies will actually “practice” crawling or standing in their crib at night instead of settling down. You might find your baby pulling up on the crib rails at 2 a.m., wide awake and seemingly energized.
This regression typically lasts two to six weeks. What separates a sleep regression from an illness is that your baby acts normally during the day. They’re alert, eating, and engaged. If your baby seems lethargic, is refusing food, has a fever above 100.4°F, or is unusually fussy around the clock, something else may be going on.
Separation Anxiety Peaks at This Age
Nine months is when most babies develop a strong understanding of object permanence, the concept that something (or someone) still exists when it’s out of sight. This is a cognitive leap, but it means your baby now fully grasps that you’ve left the room. The result is separation anxiety, and it hits hardest at bedtime and during night wakings.
Your baby may cry intensely when you put them down, cling to you when you try to leave, or wake up multiple times just to confirm you’re still there. This is completely normal brain development, not a behavioral problem. Some babies skip this phase entirely at nine months and don’t experience separation anxiety until 15 or 18 months, so the timing varies. If your baby is also hungry, overtired, or feeling under the weather, the separation distress will be more intense.
Teething May Be Part of It
While baby teeth can start emerging as early as four months, many nine-month-olds are actively cutting teeth. Teething pain tends to be worse at night because there are fewer distractions. Signs that teething is contributing to your baby’s sleep trouble include excessive drooling, chewing on hands or objects, swollen or inflamed gums, and a drool rash on the face or neck. A slight temperature elevation up to 100.4°F can accompany teething, but anything higher points to illness rather than teeth.
Teething discomfort is real but usually short-lived for each tooth. If your baby’s sleep has been disrupted for weeks on end, teething alone probably isn’t the full explanation.
Your Baby’s Schedule May Need Adjusting
By nine months, most babies are ready to drop from three naps to two. If your baby is still on a three-nap schedule, that third late-afternoon nap could be the reason bedtime has become a battle. Signs your baby is ready to drop a nap include shorter naps, resisting the last nap of the day, fighting bedtime, and consistently sleeping less than 10 hours at night.
At this age, most babies do best with about 2 hours and 45 minutes to 3 hours and 30 minutes of awake time between sleep periods. If wake windows are too short, your baby won’t have enough sleep pressure to fall asleep easily. If they’re too long, your baby becomes overtired, which paradoxically makes sleep harder, not easier. An overtired baby produces more stress hormones, which leads to more night waking and shorter naps.
Infants between 4 and 11 months need 12 to 16 hours of total sleep per day, with naps typically accounting for 2 to 3 hours of that. If your baby is getting significantly less, their schedule likely needs restructuring.
Increased Calorie Needs
This one surprises a lot of parents. Crawling, pulling to stand, and cruising burn far more calories than lying or sitting. Some nine-month-olds start waking at night genuinely hungry because their daytime intake hasn’t kept up with their new activity level.
If your baby wakes and feeds voraciously (not just comfort nursing or taking a few sips), that’s a strong signal they need more calories during the day. Increasing breastmilk, formula, or solid food during waking hours can solve night wakings that no amount of sleep training will fix. A hungry baby will wake up no matter how perfect the sleep environment is.
What You Can Do Right Now
Start with the sleep environment. Your baby should sleep on their back in their own sleep space, on a firm, flat mattress with a fitted sheet. No loose blankets, pillows, stuffed animals, or crib bumpers. Avoid letting your baby fall asleep in swings, car seats (unless actually in the car), or on couches or armchairs. A consistent, boring sleep space signals to your baby’s brain that it’s time to rest.
For separation anxiety, practice short separations during the day. Leave the room briefly and come back, building your baby’s confidence that you always return. At bedtime, keep your goodbye routine consistent and calm. Lingering or sneaking out both tend to backfire. A predictable, brief routine works better: a few minutes of winding down, a clear goodnight, and then leaving.
If you suspect teething, a chilled (not frozen) teething ring before bed can help numb sore gums. Gently wiping drool from your baby’s face and neck prevents the rash that adds to their discomfort.
For schedule issues, try shifting to two naps if you haven’t already, with the first nap mid-morning and the second early afternoon. Move bedtime earlier to compensate for the lost third nap. Many parents resist an early bedtime, but a 6:30 or 7:00 p.m. bedtime often produces longer, more consolidated nighttime sleep than a later one.
How Long This Lasts
Most nine-month sleep disruptions resolve within two to six weeks as your baby adjusts to new skills, adapts emotionally, and settles into a new schedule. The key is avoiding habits during the regression that you’ll need to undo later. If you start bringing your baby into your bed, nursing to sleep every waking, or rocking for 45 minutes each time, those patterns can outlast the regression itself.
That said, survival matters too. If you need to do what works to get through a rough stretch, the world won’t end. Just be intentional about gradually returning to your baby’s normal routine once the worst passes. Sleep regressions feel endless in the middle of the night, but they are, by definition, temporary.