What are ovarian cysts from?

Most are normal: Making cysts is what the ovary normally does. Ovulation is the process by which an egg is enclosed in a follicle that produces estrogen. The follicle develops over (usually) two weeks, and then ruptures, releasing the egg. This is ovulation. The structure that was the follicle the begins to produce progesterone. It remains present until 10-12 weeks if pregnancy occurs.