Top 7 Causes for 9 Month Old Babies' Sleep Regression

Baby sleeping in crib wearing a Woolino sleep bag.

Sleep regression is the time when a baby who was sleeping consistently experiences a temporary period of waking frequently in the night; is likely to wake earlier from naps and is harder to calm. Sleep regression usually lasts from 3 to 6 weeks. Common sleep regressions occur at 4 months, 9 months, and 18 months. Understanding your 9 month old’s sleep regression is the key to restoring a restful routine.  It’s also an opportunity to establish a sleep routine if it has been lacking.  If you’ve come to the conclusion that waking multiple times a night is not conducive to winning the “Parent of the Year” award, then the following information will help you sleuth out the reasons for your 9-month (or 8 or 10 month) old’s restlessness, and help you develop a plan that will get everyone back to blissful sleep.

Physical Developments

Your 9-month old’s brain is growing like the proverbial weed. Language is being absorbed.  Physical skills like crawling, sitting up, scooting, pulling up, and cruising are milestones at this age. This requires a lot of Baby’s energy and focus.  All this excitement can make it difficult for your child to settle down for naps and bedtime. If timed well, the physical energy expended on these new skills can tucker the child out and work in your favor. Just make sure playtime doesn’t overlap with your 9 month old’s nap schedule or bedtime so that your baby can unwind before going to sleep.

Change in Sleep Needs

9-month old babies still need 11 to 12 hours of sleep per night and 2-3 hours of nap time during the day at this age, but the nap time may need to be modified from your previous schedule to accommodate a more active baby.  Fewer naps mean baby may be a bit crabby until you reestablish your 9 month old’s sleep schedule.


Teething is an ongoing struggle that will plague some children’s sleep on and off for the first two years of life. Other babies don’t seem to be as bothered by their pearly whites popping through.

Teething can make babies uncomfortable and therefore resistant to sleep. Check for new tooth buds and treat the child’s discomfort before laying them down to rest. Topical oral gel treatments with benzocaine are unsafe and not recommended by the FDA. The American Academy of Pediatrics recommends alternative ways for treating teething pain, including rubbing your infants’ gums with a clean finger or providing a teething ring made of firm rubber to chew on. If that doesn’t soothe aching gums, then reach out to your pediatrician for advice on pain relievers that might be appropriate.

Physical or Medical Discomfort

Is your 9 month old crying uncontrollably at night? Never discount the fact that your child’s discontent could also be due to physical discomfort caused by an illness. Fevers, stuffy noses, and aching ears can keep your baby from the sound sleep you both need.  This could be the root of temporary sleeplessness, but should correct itself as symptoms are relieved and the baby returns to good health—unless of course, you’ve established some unintentional habits during the illness, such as co-sleeping, rocking or nursing your child to sleep.  Babies may be resistant to change once on the mend. The sleep training techniques you’ve used in the past may have to be reestablished.

The little one is too hot or too cold

With the change of the seasons comes temperature changes, so you may need to reevaluate how you are dressing your baby for bed. Woolino sleep bags provide comfortable four-season sleep-time temperature regulation in any season with the simple adjustment of what your baby wears under their Woolino sleep bag.


Active, growing babies that happily skip their nap may suddenly meltdown due to overtiredness.  Naps may not need to be as long or as frequent, but to avoid cranky babes who are unable to settle down, you’ll want to reestablish a routine that fits their needs and doesn’t leave them sleep-deprived during the day and unable to settle in the evening.

Baby Doesn’t Have a Good Routine

If you have never had a routine, and now there is more baby fussiness and less contentment, you may find a bedtime routine will do the trick.  To ensure your child does not become overtired during the day and restless at night, there are several methods of sleep training you may find helpful for establishing a routine that will have you both resting peacefully.