Estrogen and Sleep Quality

As women transition into menopause, sleep disorders become more common. They may have trouble falling asleep and staying asleep. In fact, studies show that menopausal women spend less time in one of the deepest cycles of sleep known as the rapid eye movement (REM) sleep. [309] This in turn results in fatigue or tiredness upon waking up. Interestingly, several lines of evidence show that ERT improves sleep quality, reduces time to fall asleep and number of times a patient awakens, and increases amount of REM sleep:
1. In postmenopausal women, ERT significantly improves sleep quality, facilitates falling asleep, and decreases nocturnal restlessness and awakenings. [310-313]
2. In postmenopausal women with sleep apnea syndrome (SAS), ERT increases REM sleep and decreases the number of waking episodes. [314-317]
3. In postmenopausal women with mild-to-moderate sleep-disordered breathing (SDB), ERT is associated with significant reduction in measures of sleep-related breathing abnormalities. [318-319]
4. In women suffering from menopausal symptoms, estrogen administration at a dose of 0.625 mg significantly improves time spent awake after sleep onset and subjective measures of sleep (questionnaires). [320-321]
5. In postmenopausal women with sleeping difficulties, ERT is associated with significant decrease in hot flushes associated with awakenings, as well as improvement in sleep efficiency and a reduction in the rate of cyclic alternating pattern (EEG marker of unstable sleep). [322]
6. In menopausal and postmenopausal women, ERT improves sleep by decreasing night time awakenings. [323]
7. In perimenopausal and postmenopausal women, ERT improves sleep quality by decreasing frequent nighttime awakenings as well as vasomotor symptoms (night sweats, hot flushes and headaches). [324-330]
8. Estrogen treatment after menopause restores the normal sleep electroencephalogram pattern in postmenopausal women. [331]