Age of Puberty.-- In the temperate regions the age of puberty is reached between the ages of twelve and fourteen years. The girl is then said to be nubile; that is, as soon as menstruation appears it is possible for her to bear children; but she is by no means sufficiently developed to do so, as she herself will not be completely developed physically or mentally before the age of twenty-two or twenty-five years.
Physical Changes at Puberty.-- The physical changes that gradually take place, beginning at the time of puberty, are: the breasts, pelvis, and neck enlarge; hair develops over the pubis and in the arm-pits; the voice alters. As a rule, women continue to grow in stature until the twenty-fifth year. It is said that brunettes develop sooner than blondes, and that large women develop more slowly than women of small stature; city girls develop younger than girls brought up in the country. Whatever stimulates the emotions causes a premature development of the sexual organs; as children's parties, late hours, sensational novels, loose stories, the drama and the ball-room, talk of beaux, of love and marriage, and children being surrounded with the atmosphere of riper years. It is generally believed that early stimulation of the sexual instincts leads to the premature establishment of puberty, as do also spiced foods and alcoholic beverages.
First Onset of Menstruation.-- Sometimes the first menstrual discharge appears suddenly, lasts for a few days, and then stops; it may appear after an interval of two or three weeks, or not for several months. If for several months the flow appears at the regular time, and the quantity is about the same as the first, the menstrual habit may be said to be established. The mode of onset varies considerably within the limits of health. So long as the general health remains good, no anxiety need be felt in regard to the establishment of the menstrual function.
In other cases there may be a discharge of blood at the first period, and none afterward for several months; in other words, menstruation may be established suddenly, intermittently, or gradually. It must be remembered that certain pathologic conditions cause many disturbances connected with the onset of puberty.