a recurring cycle (beginning at menarche and ending at menopause) in which the endometrial lining of the uterus prepares for pregnancy; if pregnancy does not occur the lining is shed at menstruation;
"the average menstrual cycle is 28 days"
双语例句
用作名词 (n.)
This increase is physiologic with a normal menstrual cycle. 这是伴随正常月经周期的生理性增生。
You can estimate your ovulation cycle, the menstrual cycle. 你可以自己测算排卵周期，即月经周期。
