Answer:
During the uterine month there are different phases through which the uterus passes, these phases are regulated by hormones and are responsible for producing the cycle necessary for fertilization.
Phase where menstruation occurs: This phase only happens if the woman was not fertilized and did not develop the diploid cell together with a sperm, since not being fertilized, all the uterine preparation that had been planned in the body for fertilization will be released as that we know "menstruation", in this phase estrogens and progesterone are low. The inner walls of the unfertilized uterus are released.
Follicular phase, in the follicular phase the ovaries prepare to release an egg and estrogen begins to rise. (From the first day of the period until ovulation)
Proliferative phase, in the proliferative phase, new vessels proliferate and the outermost layer of the uterus prepares itself for possible fertilization, is where spiral arterioles can begin to form again in the external cut of the myometrium.
Ovulation, here is where the mature ovum is called Graff's follicle, at this time estrogen reaches its peak and then descends.
Luteal phase, in the luteal phase the production of the luteal body is generated, at this stage progesterone takes center stage, and it is the range between ovulation and menstruation (if not fertilized)
Last phase, secret phase, in this phase there are two possible ends, if the woman is fertilized, the egg cell implants and begins the development of the embryo and if it is not fertilized, the entire external cut of the myometrium is prepared to be secreted.
Step-by-step explanation:
A very important fact to clarify is that women are born with a quantity of ovules that at the end of this uterine cycle ceases to exist, this process is what we know as menopause.
That is to say that women have a quantity of ovules that will one day run out, and the body releases them from the menarche or the first menstruation, generating that in each released ovule a uterine cycle is completed, the day they end the woman will have reached menopause and would have no chance of being fertilized or completing the uterine cycle.