The ovarian cycle describes the monthly events of a post-pubescent ovary that causes a small number of primary follicles to grow,

The ovarian cycle regulates endocrine tissue preparation, and egg release in female body.  

The first half of the ovarian cycle as the follicular process. Slowly growing rates of FSH and LH are causing follicle development on the ovary surface. This cycle makes the egg primed for ovulation. As the follicles develop they start releasing estrogens and low progesterone levels. Progesterone locks the endometrium in order to help ensure pregnancy. It takes about seven days to travel ovum through the Fallopian tube and to get implanted in uterus. There are 30-60 cells at this point of evolution, called the morula. If there is no pregnancy implantation the lining would be sloughed off. estrogen levels increase after around 5 days, and the menstrual cycle enters the proliferative process. The endometrium starts to regrow, replacing the weakening blood vessels and glands at the end of the last cycle.

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