Menstrual phase (days 1 - 5)
The top layer of the ' uterus , called endometrium, go to necrosis (cell death) and is separated into strips, leaving exposed the veins and arteries in it shall run. Therefore there is a loss of about 40 milliliters of blood mixed with necrotic debris cellular endometrium. At the same time, the ovary begins the growth of some follicles, and increases the secretion of FSH , or Follicle-Stimulating Hormone , produced by ' pituitary glands in the female determines that the maturation of the follicle and stimulates the production of estrogen by the ovary.
Proliferative phase (days 6 - 14)
Reconstitutes itself the surface circulation in the uterus endometrium and the layer of epithelial cells lining the vagina thickens to create a favorable environment for sperm .
ovary, one follicle continues to mature, while others go to meet 'involution.
Estrogens increase greatly until it reaches a peak just before ovulation and then decreases rapidly. Progesterone, another hormone secreted by the ovary, it increases slowly. The FSH decrease before rising just before ovulation occurs while a strong increase of LH , or hormone Lutenizzante, also produced by the pituitary and which cooperates with FSH in maintaining the normal production of estrogen by the ovary as well to determine the formation of the corpus luteum after ovulation and stimulate the production of progesterone.
Ovulatory phase (days 14-15)
In utero, the ' endometrium reaches its maximum thickness, the ovary is the breaking of the follicle and expulsion of the egg in it is contained; estrogen rapidly decrease and progesterone continues to rise. The basal body temperature, and then measured in the morning when most alarm clocks with a special thermometer to be inserted into the vagina, it was extended by about half a degree.
This measurement is based methods of temperature measurement baseline that some women use to determine the exact time of ovulation. One must remember that this method can not absolutely be effective for contraception, for the fact that the majority of women have regular cycles, but rather can be very useful when you want to schedule a pregnancy . Therefore, it is far from clear that all women, three days after the slight rise in temperature, can be considered no more fruitful.
Early secretory phase (days 16 - 23)
In the uterus, endometrial epithelium remains at the maximum of its thickness; in the vagina, instead, the epithelium thins; is formed in the ovary the corpus luteum; estrogen and progesterone increase, decrease, while FSH and LH.
Late secretory phase (24 - 28 days)
Ovary begins regression of the corpus luteum, estrogen and progesterone decrease as FSH and LH levels remain low.
The reduction in the levels of progesterone leads to the disintegration of the mucous uterus (endometrium), then to menstruation, at which point the menstrual cycle may start over.
