最近一项研究表明，处在绝经早期阶段的女性更容易发生睡眠障碍。绝经期转换的最早阶段叫作更年期，处在这一阶段的女性由于体内激素水平的波动，月经周期容易出现异常，还可能发生睡眠障碍和潮热。近日，相关研究结果发表在国际学术期刊JCEM上。

　　这项研究对月经周期中黄体期和卵泡期产生的激素波动如何影响睡眠进行了检测。结果发现更年期女性在月经到来之前的黄体期更容易产生睡眠障碍，而在月经期之后的阶段这种现象会得到改善。通过对志愿者的大脑活动进行检测可发现，即使是对于处在生育最后阶段的更年期女性来说，孕酮仍然会影响女性睡眠。

　　参与该项研究的女性都要在睡眠实验室睡两次--其中一次是在月经期开始之前的几天，而另一次则是在月经期之后的几天。研究人员利用脑电波图像对志愿者的睡眠和脑活动进行了监测，同时，每一位参与者还在进行实验室监测之前填写了睡眠质量调查表，并进行了血液检测分析了血液中的激素水平。结果显示在月经到来之前，志愿者们的深度睡眠更少，更容易醒来，同时她们的孕酮水平更高，而在月经之后的一段时间里，这种现象得到改善。与此相比，年轻女性在整个月经周期中的睡眠都更加稳定。

　　研究人员最后指出，对于中年女性来说，月经周期中激素的变化仅仅是影响睡眠质量的一部分因素，而这项研究对于更好地理解更年期女性睡眠障碍问题提供了重要信息。

　　DOI: http://dx.doi.org/10.1210/jc.2015-1844

　　Menstrual Cycle-Related Variation in Physiological Sleep in Women in the Early Menopausal Transition

　　Massimiliano de Zambotti, Adrian R. Willoughby, Stephanie A. Sassoon, Ian M. Colrain, and Fiona C. Baker

　　Context:

　　Most studies show sleep homeostasis and continuity remain stable across the menstrual cycle in young women. The influence of the menstrual cycle on physiological sleep in midlife women is unknown.

　　Objective:

　　The objective of the study was to assess the impact of menstrual cycle phase on the polysomnogram and electroencephalographic (EEG) features of sleep in midlife women, accounting for the presence of an insomnia disorder.

　　Design and Participants:

　　This was a laboratory study of 20 women in the early menopausal transition (48.8 ± 2.9 y), 11 with a Diagnostic and Statistical Manual of Mental Disorders, fourth edition, diagnosis of insomnia, studied on one night each in the follicular and luteal menstrual cycle phases.

　　Main Outcome Measures:

　　Polysomnographic and sleep EEG indices were measured.

　　Results:

　　Both groups of women had more awakenings (P = .003) and arousals (P = .025) per hour of sleep and less percentage slow wave sleep (P = .024) when progesterone was raised (≥3 ng/mL?1) during the luteal compared with the follicular phase. Both groups had greater spindle density (P = .007), longer spindles (P = .037), and increased 14-17 Hz EEG activity in the luteal phase (P <.05), although for the 15- to 16-Hz bin, this effect was significant only in women without insomnia (P <.001). Women with insomnia had a shorter sleep duration (P = .012), more wakefulness after sleep onset (P = .031), and a lower sleep efficiency (P = .034) than women without insomnia, regardless of menstrual cycle phase.

　　Conclusion:

　　Sleep is more disrupted in the luteal phase compared with the follicular phase in midlife women, whether or not they have an insomnia disorder. There is a prominent increase in sleep spindles and spindle frequency activity in the luteal phase, likely an effect of progesterone and/or its neuroactive metabolites acting on sleep regulatory systems.