In healthy women sleep disturbances occur twice as often as in men.
May 4, 2010
Insomnia, an all too common problem, is usually attributed to stress, depression, anxiety, alcohol or caffeine use, poor sleep hygiene, restless legs syndrome, and sleep apnea. Hormonally, thyroid abnormalities, and unusually low levels of melatonin can cause insomnia as well. While all of these syndromes should be considered in evaluating insomnia, the role that PMS and female hormones (progesterone, estrogens) play in insomnia is rarely discussed.
In healthy women sleep disturbances occur twice as often as they do in men. Insomnia is also often more common in the 1-2 weeks before menstruation begins (the luteal phase of the cycle), when compared with the first half of the menstrual cycle. The sleep regulating role of female hormones looms even larger in women with PMS (also known as PMDD, premenstrual dysphoric disorder), and women in the post-menopausal and postpartum phases of the reproductive cycle.
The most common finding in studies of healthy menstruating women is a reduction in dream sleep (REM sleep) in the luteal phase of the monthly cycle. REM sleep usually occurs at the time of the night when body temperature is lowest, but progesterone raises body temperature, thereby (presumably) reducing REM sleep. It is possible that variations in progesterone (which acts in some ways like valium acts, at the GABA-a receptor) and its metabolites may affect sleep quality directly, or via affects on body temperature. In sum, it seems that progesterone, the hormone that rises to very high levels (in the second half of the cycle) to prepare women for pregnancy, helps women fall asleep better, and stay asleep better (but dream less).