Baby and Sleep
A newborn may sleep as much as 16 hours a day (or even more), often in stretches of 3 to 4 hours at a time. And like the sleep all of us experience, babies have different phases of sleep: drowsiness, REM (rapid eye movement) sleep, light sleep, deep sleep, and very deep sleep. As babies grow, their periods of wakefulness increase.
At first, these short stretches of 3 to 4 hours of sleep may be frustrating for you as they interfere with your sleep pattern. Have patience - this will change as your baby grows and begins to adapt to the rhythms of life outside the womb.
At first, though, the need to feed will outweigh the need to sleep. Many pediatricians recommend that a parent not let a newborn sleep too long without feeding. In practical terms, that means offering a feeding to your baby every 3 to 4 hours or so, and possibly more often for smaller or premature babies.
Breastfed infants may get hungry more frequently than bottle-fed babies and need to nurse every 2 hours in the first few weeks.