1. Summary of the Events of the Menstrual Cycle

3. Days 1-5 Menstrual Phase Superficial layer of the uterus is removed
Bleeding occurs for three to five days
Average blood loss is mL
By day 5 growing ovarian follicles begin to produce estrogen and the removal of the uterine lining ceases

5. Days 6-14 Proliferate Phase
Rising levels of estrogen produced by the developing follicles stimulates the regeneration of the functional layer of the uterus
Glands form in the new layer and the blood supply to the layer increases
Ovulation occurs at the end of this phase (Day ) due to the surge of LH in the blood
For the next 7 days the individual will be at their peak chance for conception

6. Days Secretory Phase
The corpus luteum of the ovary begins to produce lots of progesterone
This increases the blood supply to the endometrium
Progesterone also causes the endometrial glands to swell up and they begin to secrete nutrients into the uterine cavity
If a fertilized egg should implant itself, these nutrients would sustain its early developmental stages

7. Days Cont.
The fertilized egg would also produce hormones similar to LH so that the corpus luteum keeps on producing its hormones to sustain it
If the egg is not fertilized, the corpus luteum will degenerate as LH levels fall
Lack of ovarian hormones in the blood also causes the blood vessels that supply the endometrium to spasm (cramps) and twist
This cuts off the supply of blood and leads to cell death
Once this happens, the menstrual period will begin again