The menstrual cycle goes through four phases from one period to the next just like the 28 day cycle of the moon. Phase 1 (New Moon) : Menstruation-The elimination of endometrium (lining of the uterus) from the body through the vagina. Menstrual fluid contains blood, cells from the uterus and mucus. This is commonly known as the period. Phase 2 (Waxing Moon) : Follicular phase-This phase starts on the first day of menstruation and ends with ovulation. the pituitary gland releases follicle stimulating hormone (FSH) which stimulates the ovary to produce around 5 -20 follicles (tiny nodules or cysts). Each follicle houses an immature egg. Usually, only one follicle will mature into an egg, while the others die. This can occur around day 10 of a 28-day cycle. The growth of the follicles stimulates the lining of the uterus to thicken in preparation for possible pregnancy.
Phase 3 (Full Moon) : Ovulation is the release of a mature egg from the surface of the ovary. This usually occurs mid-cycle, around two weeks or so before menstruation starts. The life span of the typical egg is only around 24 hours. Unless it meets a sperm during this time, it will die.
Phase 4 (Waxing Moon) : Luteal phase- Starts after ovulation and ends with the first day of your period. Once the follicle has released its egg, the follicle itself then changes. The empty sac closes off, turns yellow, and transforms into a new structure called the corpus luteum. If you get pregnant, your body will also start to produce human gonadotropin (hCG). This hormone maintains the corpus luteum. If you don’t get pregnant during this phase, the corpus luteum will shrink and die, the uterine lining will shed during your period & the entire cycle will repeat.