The period from onset of one menstrual bleeding (menstruation) to the next in an ovulating woman or female primate. The menstrual cycle is regulated by endocrine interactions of the hypothalamus; the pituitary gland; the ovaries; and the genital tract. The menstrual cycle is divided by ovulation into two phases. Based on the endocrine status of the ovary, there is a follicular phase and a luteal phase. Based on the response in the endometrium, the menstrual cycle is divided into a proliferative and a secretory phase.