For the elucidation of the manifold reflex and other processes which are dependent upon or accompany the sexual phases of woman, we must in the first place consider the anatomical changes and physiological functions of the female reproductive organs characteristic of the several periods of sexual life which have already been distinguished. We must not fail also to take into consideration the mental states which accompany and characterize these respective phases. The anatomical changes which occur in the female genital organs during these different phases of sexual life give rise to a number of manifold local stimuli, increasing and decreasing, varying greatly in intensity and area of distribution, upon which depend the reflex effects and remote manifestations in the sphere of the nervous and circulatory systems. We must first consider the changes in the ovaries, which play an etiologically important part. At the onset of puberty, the follicular masses of the ovary exhibit a more active growth, the follicles increase in size, with their contained ova they approach the surface, and finally, by the bursting of the follicles, the ova are extruded. Then, in the life-phase in which conception occurs, and under the influence of the hyperæmia of all the pelvic viscera that accompanies this process, a notable development of the corpus luteum takes place, this latter body reaching its maximum size in the eleventh week of pregnancy, subsequently undergoing involution and leading to the formation of a considerable scar. Finally, in the critical period of life in which the menstrual flow ceases, a continually increasing growth and new formation of connective tissue-stroma takes place in the ovaries at the expense of their cellular constituents, and a regressive metamorphosis of the graafian follicles occurs. In association with these sexual processes there ensues a series of striking changes in the shape and consistency of the ovaries, affecting both the surface and the parenchyma of these organs, and capable of stimulating the nervous ramifications in their tissue. In this connection it is worthy of note that the branches supplying the ovaries from the spermatic plexuses of the sympathetic contain a considerable proportion of sensory fibres. Quite as significant, moreover, as the changes in the ovaries, are those which, in the course of the sexual life, the uterus undergoes, in shape and size, in its muscular substance and mucous lining, and in its vascular and nervous supply. [Illustration: FIG. 2.—Portion of the pelvic viscera in the female, and their relation to the muscles of the pelvic outlet (or perineal muscles), shown in the left half of the pelvis, seen from the right side.—The parametrium. (From Toldt: Atlas of Human Anatomy.—Rebman Company, New York.) ]