In theory,

In theory, "through the night" means sleeping the walking company at least 5 hours straight between 23h and 5. In fact, people who ask this question rather want to ask if the baby makes "our night" adult, that is to say, if he sleeps at least 7 or 8 hours straight at night. Many even want to know about this issue if the baby makes the "night child", that is to say, if he sleeps continuously between 10 and 12 hours per night, the walking company or 19-20h-7h about 6, question of giving respite to parents (time with family) in the evening, and the ability to sleep at night. So you can see that there is a large gap between what is expressed by sleep specialists and what is expected by parents.
However, in theory, to 3 or 4 months (and 2 months), the baby is able to sleep through the night and ready to do so. It is up to parents to give them the opportunity for healthy habits and a reassuring routine. Of course, we are talking the walking company about 5 or 6 hours of continuous sleep, remember, but it is not this that include a large number of parents who expect their baby to sleep without the walking company interruption 7 - 8h or 10-12h, at this age. This gap between expectations and reality becomes a great source of stress the walking company and potential frustration. Or the baby may be described as "difficult" and "capricious" or parents live a great guilt and feelings of incompetence in front of their failure to do their baby to sleep properly. In both cases, there is discomfort.
It seems therefore important to make an overview of what the sleep of a baby, this is normal and is a healthy expectation of parents ... and of course what we can do for your baby and parents sleep in harmony.
Let's first sleep adult ours, which will serve as a reference point and then explore the baby. * The adult needs to sleep around 8-9am period of 24 hours, including almost all (7-8am) continuously during the night, the rest (if necessary) being consumed as nap. Sleep is divided into cycles in adults, have a duration of about 90 minutes each. A good night's sleep allows the adult to bind 5 or 6 cycles of complete the walking company sleep. These cycles, who sometimes sleeps through a short period called "transitional sleep," a near-saver that lasts from a few seconds to a maximum of ten minutes state. the walking company It is during this transitional sleep you can look at your alarm clock, see that you have delicious hours of rest before you and sleep immediately (though you were not really the walking company awake).
Sleep itself is divided into two types. The first REM sleep is often called deep sleep. It is characterized by immobility of the eyes under the eyelids, and peace of the body in general. The second, active sleep, is often called paradoxical sleep or light sleep. It is characterized by rapid eye movements under the eyelids. This is the stage of sleep during which dreams occur.
When an adult falls asleep, he first comes into REM sleep. The first REM sleep lasts between 90 and 110 minutes and allows it to pass through four stages of increasingly deep (more relaxing). The first sleep cycle is completed by a 10-minute active sleep. Then begins a second cycle. REM sleep predominates the walking company so strongly at the beginning of the night, but every cycle, the proportion the walking company of active sleep increases. In the last cycle of sleep, slow and active sleep have a duration approximately equal, active sleep for up to 60 minutes. In total, during the night, the walking company adults spend 80% of their time in REM sleep and 20% in active sleep.
Baby's sleep, it is really different. First, the newborn baby has no circadian organization, that is to say it does not differentiate between day and night. There will acquire this ability only later, around 3 or 4 months. The majority of newborns will even have their longest period of awakening in the evening, the walking company when their parents start to want to go to bed, precisely because they have become accustomed during intrauterine life to s' the walking company awaken when mom went to bed (since when she walked and moved, he was lulled asleep, and therefore inclined to sleep during the day and awake at night).
Second, the walking company even if the baby needs more daily sleep than adults (16 to 18h for a newborn up to 15h 13 to 18 months, about 12 during the rest of childhood), cycles infant sleep are frankly shorter than those of adults: they only last 50 minutes on average. the walking company This is partly due to the fact that the baby's the walking company needs in active sleep are much higher. Indeed, shorter cycles allow the baby to pass 50% of their sleep time in so