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Lectures on Diseases of Women. Am. ed., p. 48. "Much less uncommon than the absence of either ovary is the persistence of both through the whole or greater part of life in the condition which they present in infancy and early childhood, with scarcely a trace of graafian vesicles in their tissue.
Then the Graafian follicles containing the ova break and these latter enter the uterus for fertilization. If fertilization takes place, the fertilized egg buries itself in the wall and development of the embryo proceeds. Menstruation stops, the calcium salts being required for the growing embryo.
The changes supposed to take place in the Graafian follicles at each menstrual period were believed to involve a peculiar expenditure of nerve force, which was so much dead loss to the individual life of the woman. The growth of the Graafian vesicle and its contained ovum was supposed to cause an irritation of the nerves of the ovary, which was reflected to the entire nervous system.
While it is not certainly known, it is probable that the ovum is capable of impregnation any time during its sojourn within the oviduct and before reaching the uterus, or probably for a period of about one week from the time of its escape from the Graafian follicle.
The bulk of the entire organ consists of connective tissue, in which lie imbedded the Graafian follicles or ovisacs, in which the ova are contained. These follicles or ovisacs are minute cells which are packed immediately beneath the surface, where they occur in all stages of development.
In the strings the young ova are distinguished by their considerable size from the surrounding follicle-cells. Two young Graafian follicles, isolated. In the male mammals there is the same fusion of the Mullerian and Wolffian ducts at their lower ends.
While it is probable that a variable number of the immature ova undergo partial development before puberty, yet the advent of sexual maturity at that time marks the establishment of the regular development of the Graafian follicles and their contained ova, accompanied by the attendant phenomena of menstruation.
It is supposed that the ovum is grasped by the fringe-like extremity of the Fallopian tube and is carried through it by the movements of the ciliary epithelium to the uterus. The formation of new follicles continues only for a short time after birth, when the Graafian follicles are the most numerous; the entire number contained within the ovaries of the child being estimated at over 70,000.
During the entire child-bearing period, or from about the age of fifteen to forty-five years, the development of the Graafian follicles and the discharge of the ova are continually taking place. The liberation of the ova usually takes place at definite times, which in general coincide with the menstrual epochs, one or more ova being set free at each period; but this is by no means invariable.
Peuch found that in one case the ovaries were of normal size three years after the establishment of the menopause. Kiwisch describes the structural change in this gland as consisting, on the one hand, of an increase of the connective-tissue stroma; and, on the other hand, the Graafian vesicles themselves undergo retrograde change.
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