Whoever coined the phrase "sleeping like a baby" must not have lived with a newborn: babies are noisy sleepers, and new parents are treated to a nightly symphony of grunts, whimpers, snorts and yelps. Grunting and other sleep noises are normal and only occasionally require a response from you; however, sometimes grunting at the end of a breath can signal a need for medical attention.
Normal Sleep Sounds
Newborn babies make noises when they breathe for the same reason adults do; some bit of mucus or dried milk is partially blocking a breathing passage. If you can't bear the noise, use a baby-size nasal aspirator to suction out the blockage. Your baby might make a gurgling sound when he's trying to clear his throat or gasp after a brief pause in breathing. You might also hear whimpers, laughs, cries or yells, the baby equivalent of sleep-talking.
Newborn babies breathe through their noses, which allows them to eat and breathe at the same time. As tiny as their noses are, the air passages inside them are even smaller, and little particles of mucus can further constrict them, causing those crazy grunts, whistles and squeaks.
Newborns are still learning how to regulate their own breathing, which can contribute to some of their alarming noises. Infants normally take about 40 breaths per minute while they're awake, but once they're asleep everything changes. Breathing rates can slow by half, or they can increase rapidly for seconds at a time. Irregular or shallow breathing, weird noises and even short pauses followed by gasps or gulps of air are normal and rarely cause for alarm--they're just the consequence of your baby's brain learning how to work out the whole breathing thing.
Dream, Dream, Dream
Babies move rapidly through sleep cycles and spend more than half their night in the REM stage, the period of light, active sleep in which we dream. Those dream phases might produce grunts, along with fleeting cries, laughs and other "sleep-talking" sounds. Babies also wake briefly at the end of each REM cycle and may make a bit of noise before settling back to sleep.
What It Means
Along with the grunting, you might have heard your baby snuffle, yelp, whimper and even cry in his sleep. Not all--not even most--of these sounds are communicative, meaning they aren't intentional and don't require a response from you.
You can help your baby sleep longer--and get a little more shut-eye yourself--if you learn to distinguish your baby's sleep noises from his awake noises. When he makes a peep during the night, wait, watch and listen to see whether he settles back to sleep or rouses fully and needs your attention. You'll soon learn which sounds mean he needs you and which you can (hopefully!) sleep through.
When to Worry
Occasional grunting is probably nothing to worry about, but a grunting sound at the end of each breath can indicate difficulty breathing, especially when it occurs with flared nostrils or visible retractions of the chest and neck muscles. If this describes your baby's grunting, consult your pediatrician.