_Frœlich_ has discussed this subject exhaustively in his monograph on _Menorrhagia of Young Girls and Hypertrophy of the Cervix Uteri_.[21] He states that the cases of menorrhagia in young girls at the time of the menarche may be arranged in two groups. In one of these the patients are chlorotic, and menstruation is normal neither in amount nor in duration, but it is the long continuance of the flow rather than its profuseness that gives rise to danger; in the cases belonging to the other group the patients are in excellent health at the commencement of puberty, but menstruation soon takes the form of long-continued and profuse menorrhagia. Cases of the latter kind are due to hypertrophy of the cervix uteri and fungous metritis. Such attacks of menorrhagia in young girls are seen also in cases of infectious disorders, as in smallpox, measles, scarlatina, and above all, influenza. The hæmorrhage often begins in the first days of the infection, and even during the period of incubation, one or two days before the appearance of the general symptoms. If the patient is attacked by influenza while menstruating, the menstrual flow may assume the character of a true menorrhagia. More often, however, in such cases, we have to do with an extra-menstrual hæmorrhage, such as may indeed be observed in girls who have not yet begun to menstruate.
Chronic metro-endometritis, both corporal and cervical, occurs occasionally in young girls during the years of development. It is especially common in chlorotic subjects; and next to these in girls who are careless about the observance of hygienic precautionary measures during the menstruation. Thus it may result from physical exertion among the working classes; and from dancing, skating, riding, or mountaineering, among girls belonging to the well-to-do classes, during menstruation. Again, we meet with it in girls who work very hard at the sewing-machine; and, finally, in those who have long practiced masturbation. Through uncleanliness at the time of menstruation, the blood with which chemise and drawers are stained and the pubic hair soiled, undergoes decomposition, and this may lead to catarrhal inflammation of the vulva and vagina and of the endometrium. The most striking symptom in persons thus affected is the discharge of mucus, which in cervical metro-endometritis leads to a very moist condition of the external genitals, and leaves greenish-yellow spots on the under-linen; in corporal metro-endometritis the discharge is of a thinner consistence, milky in appearance, and not very abundant. As a result of the endometritis, the patient suffers from various pains in the body, a feeling of fulness, sacrache, general sense of fatigue, and diverse nervous manifestations; sometimes also from dysmenorrhœa, strangury, or obstinate constipation. In consequence of the great thickening of the mucous membrane that often occurs, menstruation becomes very profuse and long-continued, lasting from one to two weeks.