It's the question we've all asked within weeks of our beautiful bundle's birth. Once the bliss of having a newborn starts to wane under the cloud of sleep deprivation, thoughts of sleep (more sleep, please more sleep!) begin to take over.
Some babies are natural sleepers; these little angel babies can knock off 10-12 hours a night at about three months old with little-to-no concerted effort from their parents. You don't hear about them much because their parents know not to mention it in public.
For the most part, babies will need to have calories in the night for up to six months of age*, beginning with feeding every three hours as a newborn to just one feed per night at four-to-six months. (*Your baby may need one night feed for a little longer if he is on the small side, and definitely longer if baby isn't holding his growth curve - if that's the case, seek the advice of a pediatrician.)
The idea of baby sleeping 12 hours straight may sound absurd to the mom of a 10-month-old who wakes 3-4 times a night for her self-declared snack time. But these wakings are not physiological. In a healthy baby, night wakings at this age are in the realm of habit and a lack of self-soothing sleep skills.
For example, babies who are breastfed to sleep or use a soother will wake fully, crying out, when they come to a normal awakening at the end of each sleep cycle. These mini-awakenings are a normal part of sleep; we all have them with little or no recollection in the morning. Babies who have already learned to self soothe wake only briefly and simply reposition themselves before starting their next sleep cycle. Babies (or toddlers) who need a "prop" - something external like a soother or breastfeeding - to fall asleep wake fully, crying out for the "prop" they intially fell asleep with.
In the case of a baby who is dependent on a sleep prop, it will take some encouragement and habit-breaking to help her learn not to wake in the night once she's past the age of physically needing night feeds. The good news is, there are more compassionate methods now than the old-school cry-it-out technique (which essentially means saying good night to your baby and not opening her door until 7 a.m. - apparently effective, but jeesh...).
The method I recommend to parents is one in which you are beside your baby supporting them with voice and touch as they learn this ever-important new skill of falling asleep. And it works, virtually every time.
So if your baby is healthy, beyond the newborn stage and is still waking every 2-3 hours, or beyond four months and waking more than once or twice, or beyond 7-8 months and is waking at all, you can assume it's an issue of habit, not physiological need. Babies will always make up the calories during the day to get all the nutrition they need.
With the right advice and a proven plan, your baby could be sleeping through the night within a week. Then you'll be the one keeping quiet at the Mommy group.