健康的育龄妇女,卵巢发生周期性变化,不断有卵泡发育、成熟、排出,同时伴有性激素分泌的变化。由性激素调控的子宫内膜,也随之发生增生、脱落和修复的周期性改变。当子宫内膜脱落出血,自阴道流出,便称为月经。一般为28￣30天行经一次,失血50毫升左右,持续3￣7天。有规律的月经 Healthy women of childbearing age, ovarian cyclical changes, there are continuous follicular development, maturation, discharge, accompanied by changes in the secretion of sex hormones. Sex hormones regulate the endometrium, but also with the periodic changes in proliferation, loss and repair. When the endometrial shedding bleeding from the vagina outflow, it is called menstruation. Generally 28 to 30 days after passing once, about 50 ml of blood loss, lasting 3 to 7 days. Regular menstruation