While breastfeeding "on demand" is the general rule, some newborns may need a little extra push. In order to establish healthy weight gain and get your milk supply up to snuff, your newborn needs to nurse about eight to 12 times in a 24-hour period. This doesn't necessarily mean that she'll want to feed every three hours on the dot. Many moms find that their babies "cluster feed," eating super-frequently during part of the day and going longer between feedings at other times. If your baby nurses constantly for a few hours and then snoozes for a few hours, it’s okay to let her sleep. Just be sure to get in those eight to 12 good feedings each day.
So how do you know whether baby needs a wake up call? Consider waking her for feedings if she isn't gaining four to five ounces each week (after day four), is falling asleep super-frequently while nursing, is jaundiced, or has less than three to four good poops in a day. (If she's gaining weight well, the poops don't matter so much.) If your baby were in the first three or four days of her life, you'd also want to wake her to feed more often if she'd lost 10 percent or more of her birth weight.
Some experts believe that babies who fall asleep quickly on the breast sometimes aren't getting milk fast enough to keep them interested. To get a faster flow, you may need to work to improve baby's latch. You can also do breast compressions to help increase milk flow and keep baby feeding for longer.
Once baby is gaining weight well, there's no need to watch the clock or worry about baby's feeding schedule. Adequate weight gain usually means your milk supply — and baby's feeding habits — are on track.