PDF(Pubmed)
Abstract：
Estrous cycles are recurring changes in therian mammals induced by estrogen, progesterone, and other hormones culminating in endometrial proliferation, ovulation, and implantation if fertilization occurred. In women, the estrous cycle is the menstrual cycle; but, unlike most mammals, the end of an infertile cycle is marked by endometrial sloughing and the start of another without an anestrous phase. Women stop cycling at menopause, while in most mammals, cycles continue until death. Epidemiologic studies identified menarche, menopause, births, lactation, and oral contraceptive (OC) use as key risk factors for ovarian, breast, and endometrial cancers. A composite variable was created to estimate the number of cycles not interrupted by events that stop ovulation. Captured by the phrase \"incessant ovulation\", repetitive cycles were first postulated to affect ovarian cancer risk and later extended to breast and endometrial cancers. These associations could be explained by cumulative effects of repetitive tissue changes within reproductive organs, immune consequences of repetitive ovulation through the glycoprotein mucin 1, and residual effects of past ovulations that enhance ovarian production of testosterone. The latter two pathways could affect the risk for cancers in other organs not considered \"reproductive\".
摘要：
发情周期是雌激素诱导的哺乳动物体内反复发生的变化，黄体酮,和其他导致子宫内膜增生的激素，排卵,如果受精，植入。在女性中，发情周期是月经周期；但是，与大多数哺乳动物不同，不育周期的结束以子宫内膜脱落和另一个没有发情阶段的开始为标志。女性在更年期停止骑自行车，而在大多数哺乳动物中，循环继续，直到死亡。流行病学研究确定了初潮，更年期,出生,哺乳期,和口服避孕药（OC）的使用是卵巢的关键危险因素，乳房,和子宫内膜癌。创建了一个复合变量来估计不被停止排卵的事件中断的周期数。被短语“不断排卵”捕获，重复周期首先被假定影响卵巢癌风险,后来扩展到乳腺癌和子宫内膜癌.这些关联可以通过生殖器官内重复组织变化的累积效应来解释，通过糖蛋白粘蛋白1重复排卵的免疫后果，以及过去排卵增加卵巢睾酮产生的残留效应。后两种途径可能会影响其他不被认为是“生殖”的器官的癌症风险。
