In the follicular phase the level of estrogen hormone increases and the egg prepares itself for release. This phase occur between the first day of period and the ovulation. When the primary follicle matures and form secondary follicle, second meiotic division starts and lead to the formation of Graafian follicle which contains a secondary oocytes. Seconday oocytes consists of a diploid DNA and is not released until the second division is not complete.
