The earlier development of the female as compared with the male at the time of puberty is a constant phenomenon, to be observed in all races, in every climate, and in all strata of society. According to the statistical data published by the authors just quoted, the age of greatest development in the respective sexes is:
| In the female. | In the male. | |
|---|---|---|
| As regards weight at the age of | 12 to 14 years. | 14 to 17 years. |
| As regards height at the age of | 12 to 13 years. | 12 to 15 years. |
| As regards respiratory capacity at the age of | 12 to 15 years. | 15 to 17 years. |
| As regards muscular strength at the age of | 12 to 14 years. | 14 to 15 years. |
Puberty occurs in the female on the average about two years earlier than in the male, and upon this difference the observed differences in growth also depend.
The menarche in the wider signification of the term includes the development which occurs at the time of puberty, and continues through a period of several months, and even years, before complete sexual maturity is attained; and includes also the time, which may be considerable, following the first appearance of the menses and before the regular rhythm of the menstrual function is established and the full development of the female genital organs is attained. This time, which forms a notable phase of the sexual life of woman, is characterized by great changes in the genital organs and in the vital processes connected therewith, by a strong tendency to suffer from a series of very various pathological changes and disorders of function in the principal organs, and a lessened general resisting power to disease—a change which finds its most definite expression in the well-established fact that in this period of life the mortality among females is much greater than among males of corresponding age. According to the statistical data of Quetelet and Smits, from the age of 14 to the age of 18 (the period of the menarche) there are 128 deaths of females for every 100 deaths of males; and even in the four succeeding years, from the age of 18 to the age of 22, the unfavorable conditions peculiar to sex are witnessed by 105 deaths of females to every 100 deaths of males.
Many authors draw a distinction between the age of puberty (from the Latin pubes, puberis), when the growth of the pubic hair occurs as an external sign of sexual development, and the age of nubility (from the Latin nubere), when the individual becomes fitted for marriage. The distinction is a partial one only, inasmuch as capacity for copulation is attained already at puberty. The law, however, maintains such a distinction, the Austrian Penal Code, for example, regarding intercourse with a female less than fourteen years old as rape, and the German Code likewise punishing carnal knowledge of a girl under fourteen.
The signs of puberty in girls were noticed and explained in very early times. From the anthropological studies of Ploss and Bartels we take the following data regarding this matter. In the Bible we read (Ezekiel, xvi, 7): “Thy breasts are fashioned and thine hair is grown, whereas thou wast naked and bare.” The early Indian physician, Susruta, refers only to the regular recurrence of menstruation as a sign of puberty. That a woman is menstruating may be known by the fact that her face is swollen and bright. In the Roman Empire Justinian ordained that all young women should be examined as to the growth or absence of the pubic hair in order to ascertain if they were ripe for marriage. The early Chinese physicians recorded that in every woman at the age of fourteen or fifteen years a monthly flow of blood from the genital organs began, the period of recurrence being thirty days. The physicians of the Talmud express themselves variously regarding puberty in women. In one place they advance as a sign of puberty the growth of the hair on the genital organs; in another they speak of the notable enlargement of the breasts, and mention as a sign of more complete sexual development that the nipples become elastic. Other Talmudists refer to the appearance of a dark brown coloration in the areola and to the enlargement of the mons Veneris as signs of puberty. Savage races regard the first appearance of the menstrual flow as the only certain sign of puberty, and among many such races this is the occasion of peculiar ceremonial rites. The attainment of puberty in savage tribes is often solemnized by the seclusion of the girls from the time of the first menstruation; they fast during the period of seclusion, which sometimes terminates in an elaborate ritual of purification.
For two reasons in particular, the period of the menarche is a time of storm and stress to women, first on account of the developmental processes in the genital organs, and secondly on account of the intellectual changes that occur at this period.
The local cause is to be found in the extensive transformation of the ovaries and the uterus, by means of which a peculiar and powerful stimulus, the menstrual stimulus, is elaborated, which has a reflex influence upon heart and brain, vascular and nervous systems, and secretory and nutritive processes. Since we know that in every premenstrual period by the growth of the follicles hyperæmia is excited in the ovary, by means of which the liquor folliculi is increased in amount, we can well understand that at the time of the menarche the ripening of the graafian follicles is accompanied by a considerable degree of hyperæmia of the ovaries and of the whole of the genital organs, now undergoing their fullest development, and we can easily see how this hyperæmia may result in manifold reflex disturbances. But in addition to these reflex disturbances, we have once more to take into consideration the as yet imperfectly known chemical processes which are associated with the ripening and development of the graafian follicles, and an abnormal course of which may give rise to a disordered constitution of the blood, manifesting itself as chlorosis or in other ways. In connection with the growth and ripening of the ova, extensive and novel demands are made on the organism, and these may well endanger metabolic processes which are not established on a very secure foundation.
The other cause is to be found in the intellectual processes which occur at this time in the youthfully receptive, highly sensitive organ of mind, the brain. The girl growing into womanhood, who with astonishment and stress has witnessed the visible changes in her body, the outward signs of puberty, as they gradually make their appearance, receives powerful psychical stimulation which cannot fail to exercise an influence upon the entire nervous system and its complex interlacements, alike in the sensory and in the motor sphere.
The degree to which these influences radiating from the genital organs make themselves manifest is chiefly dependent upon the resisting power of the nervous system as a whole, upon the temperament, the inherited constitution, and the mode of education of the young girl. In children belonging to families noted for sensibility and irritability, in dwellers in large cities who have attended high schools for girls and have at an early age lifted the veil that covers the sexual processes, the reflex disturbances of the menarche will be more manifold and will manifest themselves with greater intensity than in children brought up in country districts, whose sensibilities are chiefly physical and whose mind is less susceptible to the influence of external stimuli.