Congratulations! Now your baby will probably begin to stay awake longer during the day and sleep more at night. Probably — but the range of normal is still very wide.

Your baby's sleep phases are much the same as your own: drowsiness, REM (rapid eye movement) sleep, light sleep, deep sleep, and very deep sleep. Your baby might start sleeping through the night now — but the definition of "sleeping through the night" at this age is a stretch of only 5 hours!

How Long Will My Baby Sleep?

Since babies are more alert and aware of their immediate surroundings during the daylight hours, they're more inclined to sleep during the night, especially if parents fight the urge to play or talk to their baby during nighttime feedings or diaper changes.

Your baby is adapting to the sleep-wake cycle that parents favor, and the baby's stomach is growing and holding more breast milk or formula. At 3 months of age your baby will likely sleep about 15 hours out of each 24-hour period, and two thirds of that sleep will take place during the night.

Most babies will have settled into a daily sleep routine of two or three sleep periods during the day, followed by "sleeping through the night" for 6 to 7 hours after a late-night feeding.

If your baby is sleeping a lot when you want him or her awake — or vice versa — encourage wakefulness during the day while also allowing your baby to have distinct sleeping periods. You also can rouse your baby for the late-night feeding at a time that suits your sleep schedule. For instance, if your baby gets sleepy after the 7 p.m. feeding and sleeps until 2 a.m. before feeding again, wake the baby to feed at 11 p.m. and then put him or her down to sleep until an early-morning feeding at 5 or 6 a.m. It may take a few nights to establish this routine, but it will happen if you're consistent.

If your baby wakes during the period that you want him or her to be sleeping, keep activity to a minimum. Change or feed your baby in the dark, and don't play with the baby. Your little one will start to get the message that you're a bore during the night, so he or she might as well just go back to sleep.

Again, not all infants keep to the same timetable. If you have questions or concerns, check with your doctor.

Where and How Should My Baby Sleep?

The American Academy of Pediatrics (AAP) recommends that healthy infants be placed on their backs to sleep, not on their stomachs. The incidence of sudden infant death syndrome (SIDS) has decreased by more than 50% since this recommendation was first made in 1992. It is now also recommended that premature infants sleep only on their backs.

It is thought that some babies sleeping on their stomachs may have a greater tendency toward sleep obstruction and rebreathing their own carbon dioxide because they're less likely to rouse themselves to change head positions. Another possibility is that they may suffocate on softer bedding if they're lying face-down.

Once your child is rolling over on his or her own, around 5 to 6 months of age, you no longer need to worry about sleep positioning. If you have difficulty getting your baby to sleep on his or her back before this age, though, talk to your doctor.

Always keep sleep safety in mind. Make sure your crib meets current safety standards. Don't put anything in the crib that can interfere with your baby's breathing — stuffed animals, blankets, or soft pillows can fall on a baby's face and become a problem. Although bumper pads were widely used in the past, they are no longer recommended. A study, using data from the U.S. Consumer Product Safety Commission (CPSC), found a number of accidental deaths appeared to be related to the use of bumper pads in cribs and bassinets. The AAP and other pediatric organizations strongly discourage the use of bumper pads in cribs to avoid accidental suffocation.

Many cultures endorse cosleeping. But studies indicate that there is a greater incidence of SIDS in households where the infant slept in the bed with the parents. Use of substances that decrease the parents' awareness, such as alcohol, also may allow a parent to roll over onto the baby.

Encouraging Sleep

If you haven't already, try establishing a bedtime routine that will be familiar and relaxing for your baby. Bathing, reading, and singing can be soothing for parents and babies and signal an end to the day. Be consistent, and your baby will soon associate these steps with sleeping.

Remember: if part of your bedtime routine is to rock your baby for half an hour, then whenever waking during the night your baby is going to expect and need that step to get back to sleep. Ideally, your baby should be put into a crib or bassinet while drowsy but still awake. This way your baby will learn to fall asleep on his or her own.

Although it may be hard at first, some experts suggest this is also the age to start letting your baby fuss for a few minutes when he or she wakes during the night. Your baby may simply be in a phase of light slumber, even though you think your baby is totally awake. Some babies squirm, whine, and even cry in their sleep before putting themselves back to sleep.

Unless you suspect that your baby is hungry or ill, try to see what happens if you leave your baby alone. It will help you all in the long run if your baby can develop the skill of going back to sleep without your help.

When to Call the Doctor

If your baby's sleep habits concern you, speak with your doctor, who can reassure you or get to the root of a physical problem that may have no other symptoms besides crankiness or sleeplessness.

Either way, the doctor can help get you on the right track . . . the one that leads to more quality sleep for your baby and for you!

Reviewed by: Steven Dowshen, MD
Date reviewed: September 2011