MRC Centre for Reproductive Health, The University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom.
Physiol Rev. 2020 Jul 1;100(3):1149-1179. doi: 10.1152/physrev.00031.2019. Epub 2020 Feb 7.
The physiological functions of the uterine endometrium (uterine lining) are preparation for implantation, maintenance of pregnancy if implantation occurs, and menstruation in the absence of pregnancy. The endometrium thus plays a pivotal role in reproduction and continuation of our species. Menstruation is a steroid-regulated event, and there are alternatives for a progesterone-primed endometrium, i.e., pregnancy or menstruation. Progesterone withdrawal is the trigger for menstruation. The menstruating endometrium is a physiological example of an injured or "wounded" surface that is required to rapidly repair each month. The physiological events of menstruation and endometrial repair provide an accessible in vivo human model of inflammation and tissue repair. Progress in our understanding of endometrial pathophysiology has been facilitated by modern cellular and molecular discovery tools, along with animal models of simulated menses. Abnormal uterine bleeding (AUB), including heavy menstrual bleeding (HMB), imposes a massive burden on society, affecting one in four women of reproductive age. Understanding structural and nonstructural causes underpinning AUB is essential to optimize and provide precision in patient management. This is facilitated by careful classification of causes of bleeding. We highlight the crucial need for understanding mechanisms underpinning menstruation and its aberrations. The endometrium is a prime target tissue for selective progesterone receptor modulators (SPRMs). This class of compounds has therapeutic potential for the clinical unmet need of HMB. SPRMs reduce menstrual bleeding by mechanisms still largely unknown. Human menstruation remains a taboo topic, and many questions concerning endometrial physiology that pertain to menstrual bleeding are yet to be answered.
子宫子宫内膜（子宫内衬）的生理功能是为着床做准备，如果着床发生，则维持妊娠，以及在没有怀孕的情况下进行月经。因此，子宫内膜在生殖和物种延续中起着关键作用。月经是类固醇调节的事件，对于孕激素启动的子宫内膜有替代方案，即怀孕或月经。孕激素撤退是月经的触发因素。月经期间的子宫内膜是受伤或“受伤”表面的生理范例，需要每月迅速修复。月经和子宫内膜修复的生理事件为炎症和组织修复提供了一个可及的体内人类模型。现代细胞和分子发现工具以及模拟月经的动物模型促进了我们对子宫内膜病理生理学的理解。异常子宫出血（AUB），包括月经过多（HMB），给社会带来了巨大负担，影响了四分之一的育龄妇女。了解导致 AUB 的结构和非结构原因对于优化和提供患者管理的精准性至关重要。这得益于对出血原因的仔细分类。我们强调了解月经及其异常的潜在机制的重要性。子宫内膜是孕激素受体选择性调节剂（SPRMs）的主要靶组织。这类化合物具有治疗 HMB 这一临床未满足需求的潜力。SPRMs 通过仍在很大程度上未知的机制减少月经出血。人类月经仍然是一个禁忌话题，许多与月经出血有关的子宫内膜生理学问题仍有待回答。
