held in place principally by the broad ligament of the uterus, which folds around them.
As in the case of the testicles of the male, they are first formed higher up in the abdomen—just below the kidneys—but before birth descend to their normal position.
The ovaries are already filled with undeveloped eggs at birth—estimated at about 100,000 in number, but in the course of their development, there are left only about 30,000 at puberty. The balance have been used up as nourishment for those that remain. But of these many thousands, only a few hundred ever become ripe and capable of growing into a new life. One ovum for every 28 days during the normal reproductive life of a woman—about thirty years—would be approximately 400 in all. The ovum was first discovered in 1827.
The ovary has a double structure, of which the central part is reddish in color, and soft and spongy in texture, consisting chiefly of blood vessels. The cortex or outer layer is gray in color and of firm texture, being composed of connective tissue. This is the essential part, as the ovisacs, or Graafian follicles are located in it. Each of these ovisacs, which are in various stages of development, contains an ovule, as the unfertilized ovum is specifically termed.
The follicles were first described by De Graaf, a Delft physician, in 1672, from whom they derive their name. Until the time of puberty, the Graafian follicles, with their tiny ova, are in practically a dormant condition. But with the beginning of puberty, when the sexual organization turns from a latent to an active state, the ovaries become correspondingly active.
Ovulation consists in the bifortnightly maturation and expulsion of a ripe ovum. Each ovum measures from one two hundred and fortieth to one one-hundred and twentieth of
