It's a part of the menstrual cycle when the over releases a right egg or ovum inside the ovum hundreds of thousands of follicles each follicle is a hollow ball of cells with the immature egg in the center the typical 28 a menstrual cycle begins on the first day of menstrual bleeding during the first seven days of the cycle a few follicles begin to grow the same time these maturing follicle secrete estrogen hormone into the bloodstream to prepare the lining of the uterus for pregnancy around day seven all of the follicle stop growing and begin to degenerate except for one this dominant follicle continues to grow and nourishes the developing egg inside it around day 12 the follicle secretes a large amount of estrogen into the bloodstream when the estrogen reaches the hypothalamus and the pituitary gland in the brain the anterior or front part of the two terry gland releases a huge surge luteinizing hormone into the bloodstream around day fourteen luteinizing hormone causes the follicle undergrow a sudden growth spurt right before ovulation that act detaches from the inside the follicle the bulging follicle releases chemicals crossingone of the tube phrobier tube to moving closer and surround the follicles the follicle swells until it bursts open he checked in the egg in fluid from the follicle into the abdominal cavity in response the thinny egg Tiny projections at the end of the phobian tunbe sweep across the ovulation site and pick up the egg microscopic Celia on the surface transport the egg to the entrance to the fallopian tube the inside the walls of the fallopian tube muscular contractions gently push the egg towards the uterus after ovulation the egg lives 12 to 24 hours so it must be fertilized by sperm from the mail during this time woman to become pregnant that dissolves away the along with the uterine lining during menstruation.