During Ovolulation the release of a mature egg from the surface of the ovary. This happens occurs midcycle about two weeks or so before menstruation starts ( a womans "period") During the follicular phase, the developing follicle causes a rise in the level of estrogen. The egg is then funneled into the Fallopian tube and towards the uterus by waves of small, hair-like projections. The life span of the typical egg is only around 24 hours. Unless it meets a sperm during this time, it will die. If it is fertilized it will move on to the uterus to implant .