Baby’s Sleep Cycles

Understanding how your baby sleeps (please refer to Sleep Habits and Routines) will help you cope with sleep problems and night awakenings. Sleep is divided into two basic stages: REM and non-REM. REM stands for rapid eye movement, a primary trait of deep sleep.

REM sleep, often called active sleep, is characterized by:

• Eyes moving under eyelids
• Irregular breathing and heart rate
• Brain activity
• Dreaming
• Relaxed muscles
• Small twitches of face, hands and legs

Non-REM sleep, often called quiet sleep, is characterized by:

• A regular heart rate and breathing pattern
• Stillness
• Less mental activity
• Very little, if any, dreaming

Non-REM sleep is divided into four stages, beginning with drowsiness and progressing into deeper sleep. In the first stages of non-REM sleep, a person can be easily awakened. In later stages, breathing and heart rate start to become more regular, and the person is difficult to wake.

Dr. Richard Ferber, the Director for Pediatric Sleep Disorders at Children’s Hospital in Boston, has defined the development of children’s sleep habits and problems. According to Dr. Ferber, babies spend about half of their sleeping time in the REM state. Usually, a baby will fall asleep and go through a phase of non-REM sleep and a phase of REM sleep, then awaken. A baby may do this several times at night. The time spent awake may last just a few seconds or a few minutes. During this time, the baby may move around, fuss or cry. Whether the baby can fall asleep again may depend on the conditions the baby associates with falling asleep.

The sleeping patterns your baby is establishing will remain throughout her or his life. Everyone, even adults, goes through minor awakenings at night, although most people don’t remember these awakenings in the morning. Viewing these awakenings as normal will help you teach your child to fall back asleep.

(Taken from Mayo Clinic Complete Book of Pregnancy & Baby’s First Year; ISBN 0-688-11761-9)