Adulthood - Sleep Throughout Life: Sleep Disorders

Content provided by the Faculty of the Harvard Medical School

Adulthood

During young adulthood, sleep patterns usually seem stable but in fact are slowly evolving. Between age 20 and age 30, the amount of deep sleep drops by about half, and nighttime awakenings double. By age 40, Stage 4 sleep has almost disappeared.

Women's reproductive cycles can greatly influence sleep. During the first trimester of pregnancy, many women are sleepy all the time and may log an extra two hours a night if their schedules permit. As pregnancy continues, hormonal and anatomical changes reduce sleep efficiency so that less of a woman's time in bed is actually spent sleeping. As a result, fatigue increases (see "Getting a good night's sleep during pregnancy," below). The postpartum period usually brings dramatic sleepiness and fatigue — because the mother's ability to sleep efficiently has not returned to normal, because she is at the mercy of her newborn's rapidly cycling shifts between sleeping and waking, and because breast-feeding promotes sleepiness. Researchers are beginning to probe whether sleep disturbances during pregnancy may contribute to postpartum depression and compromise the general physical and mental well-being of new mothers.

Women who aren't pregnant may experience monthly shifts in sleep habits. During the second phase of the menstrual cycle, between ovulation and the next menses, some women fall asleep and enter REM sleep more quickly than usual. A few experience extreme sleepiness. Investigators are probing the relationship between such sleep alterations, cyclic changes in body temperature, and levels of the hormone progesterone to see whether these physiologic patterns also correlate with premenstrual mood changes.

Getting a good night's sleep during pregnancy According to a National Sleep Foundation poll, nearly 8 in 10 women reported more disturbed sleep during pregnancy. Here are some tips to help you get a better night's sleep when you're expecting: Avoid spicy, fried, or acidic foods (such as tomato products), which contribute to heartburn. If you have heartburn, elevate your pillow or raise the head of your bed by placing blocks under the bedposts. Prevent nausea by eating frequent snacks during the day. If you feel drowsy, take a midday nap. Exercise regularly, which will help reduce leg cramps and improve sleep. Cut down on fluids before bedtime to reduce nighttime trips to the bathroom. Use pillows or special pregnancy cushions to support your abdomen.

Last updated:	January 23, 2007