A woman's faculties physical, moral and intellectual are more profoundly influenced and controlled by her sexual functions than are those of man, she being by far more subservient to her corporeal condition; and there are few diseases which affect her without having a reciprocal effect on her sexual organs, and vice versa. Thus, during the thirty years of her reproductive life, or distinctive sex-life, the utero-ovarian functions dominate her career, and both influence and are influenced by every vital process.
Compared with woman, man's reproductive organs have a more subordinate effect on his organization; and yet, if the functions of these are abused, his life may be embittered by mental and physical disorders which make him a fit object of study for the alienist and pathologist. We must consider a little more fully the distinctive changes which occur in the boy and in the girl with the accession of puberty.
Changes in the Male. Before puberty the boy is normally entirely free from all sexual thoughts or impressions. The small and ill developed penis is covered with an elongated prepuce, and the testicles are very slightly sensitive to pressure. But at puberty there is a determination of blood to the generative organs, so that the penis, testicles and scrotum enlarge, and semen, with its accessory fluids, is secreted, and there then occurs an unmistakable manifestation of the sexual instinct. Not infrequently the mammary glands enlarge at the time of puberty and become sensitive to the pressure of the clothing, and in rare cases they secrete milk.
The voice is characteristically altered, so that the "thin, childish treble becomes a deep, manly bass"; this is due to the growth of the thyroid cartilage ("Adam's apple"), which becomes prominent, and to the lengthening of the vocal chords, so that the voice becomes hoarse, or husky, and "breaks" until it falls a full octave in its register.
A coarser hair takes the place of the "down" on the pubes, face, chest, arms, legs, axillae and other parts of the body, and the sebaceous glands develop and become active, especially on the nose, back and face.
These changes succeed one another so slowly that full sexual vigor is not attained until adolescence has passed. From puberty onward, all through the sexual life, spermatozoa are constantly being formed in the testicles, and emissions of semen occur physiologically from time to time. Gradually the type of mind and body assumes the manly features, and at twenty-five years of age the male may be considered as sexually mature.
Changes in the Female. The transition from girlhood to womanhood occurs with a bound, so that the female undergoes the sexual alteration several years before the male. In her the changes in the bodily structure and in the functions of the whole system are vastly more complex and important.
Vascularization, or the increase of blood supply to her internal and external generative organs, is of course more abundant and lavish than in the male, because of the greater area to be supplied and the greater importance of the functions of the uterus, Fallopian tubes, ovaries and breasts. At this time the skeleton and contour of the body become modified and assume the characteristic feminine appearance.
The hips become broader for the requirements of childbirth; the breasts notably increase in size and become prepared to secrete milk; the sebaceous glands become more active, as in the boy; coarse hair grows over the pubes and in the axillae; the chest increases rapidly in size, with a corresponding increase of vital capacity; the larynx becomes elongated, and there is an increased compass of voice, though it is not lowered in its register, nor does it "break" as in the boy, but becomes more liquid, musical, tender and gentle. She becomes more shy before the opposite sex, her romping tendency is subdued, and her whole "form and expression assume the characteristic sexual appearance, while the psychical energies also receive an impulse."