Objective: To evaluate the effect of estrogen replacement therapy on sleep architecture, arousals, and body movements. Design: A 7-month, prospective, randomized, double-blind, placebo-controlled crossover trial. Setting: Departments of obstetrics and gynecology and a university sleep center in Turku, Finland. Patient(s): Seventy-one postmenopausal women, 4 of whom were excluded and 5 of whom withdrew from the study; the final study group consisted of 62 women. Intervention(s): Two periods of treatment with either estrogen or placebo. Main Outcome Measure(s): Polysomnography for measurement of sleep and arousals and a static charge-sensitive bed for monitoring of movements and breathing. Self-reports of climacteric symptoms for 14 days. Result(s): Estrogen effectively alleviated hot flashes, sweating, sleep complaints, and headaches. Estrogen decreased the total frequency of movement arousals but increased alpha-arousals, especially during light non-rapid eye movement sleep (stage 1). Sleep latency, distribution of sleep stages, sleep efficiency, and total sleep time were similar during treatment with estrogen and placebo. Changes in serum E2 concentration s correlated with neither subjective nor objective sleep quality. Conclusion(s): Estrogen replacement therapy improves objective sleep quality by alleviating the frequency of nocturnal movement arousals. It also reduces climacteric symptoms, especially vasomotor symptoms. Estrogen replacement therapy does not seem to have any effect on sleep architecture.
Polo-Kantola, P., Erkkola, R., Irjala, K., Pullinen, S., Virtanen, I., & Polo, O. (1999). Effect of short-term transdermal estrogen replacement therapy on sleep: A randomized, double-blind crossover trial in postmenopausal women. Fertility and Sterility, 71(5), 873–880. https://doi.org/10.1016/S0015-0282(99)00062-X