The ovaries are lobe-like structures which are responsible for generating the mature ova, or eggs, in the female reproductive system. They are about the same size as the testes in the male, being about 2.5 cm wide and 3.8 cm long. The ovaries are located on either side of the pelvic cavity and are attached to the fallopian tubes and the upper margin of the uterus by the ovarian ligaments. Within the ovaries are a number of small sacs, called graafian follicles, which contain the maturing ova. The ovaries produce a mature ovum about once every month. When this occurs, called ovulation, the follicle containing the mature ovum erupts from the surface of the ovary and the ovum passes into a fallopian tube. If the ovum is fertilized, the graafian follicle then develops into a corpus luteum. If the ovum is not fertilized, the follicle disintegrates into a small scartissue, called a corpus albicans. In addition to generating the mature ova, the ovaries also produce female sex hormones, such as estrone and estradiol, which regulate mammary growth, placental development, and menstruation. Research Ovaries