and among the latter the discharge was
| Scanty and for the most part pale in | 511; that is | 12.250 per cent. |
| Profuse or profuse and coagulated in | 838; that is | 18.428 per cent. |
| Variable in | 196; that is | 4.315 per cent. |
Investigation regarding the individual variations that occur in this respect among women, showed that blondes usually menstruate more profusely than brunettes, and that in the former also the duration of the individual periods is longer.
The loss of blood must be considered less in respect of its absolute quantity than in respect of the effect which continued observation shows its loss to have upon the organism. If the loss of blood continues to have an effect after the flow has ceased, if a woman recovers but slowly, or even fails to recover fully from one loss before another begins, if symptoms of increasing anæmia become apparent, the bleeding must be regarded as a pathological perversion of normal menstruation. Pathological is it also if the menstrual flow does not exhibit the normal slowly rising and slowly declining curve, but sets in profusely, ceases or almost ceases for a time, and then again suddenly recurs. In some cases the flow is not profuse, but lasts for a long time, and owing to this long duration it has a debilitating effect, especially in anæmic and chlorotic individuals.
As a rule, in normal menstruation, the admixture of the alkaline cervical mucus suffices to keep the menstrual discharge fluid and to prevent the formation of fibrin. On the other hand, the discharge of coagulated masses of blood will alone suffice to indicate an abnormally free and rapid flow of blood.
The commonest type of menstruation is the more or less regular recurrence of the flow at intervals of twenty-eight days. Variations in this respect are, however, very frequent, and are dependent upon constitution, position in life, and race. In general it may be said that in persons of strong constitution, the type of menstruation is much more regular, than in persons of a weakly, delicate constitution; that in vivacious, ardent natures the menses more readily anticipate the expected period of their return, whereas in those of a flaccid, lymphatic temperament a retardation is more likely to occur; and that amongst women of the upper classes of society the type of menstruation is far more frequently irregular than amongst women of the working classes and amongst countrywomen. Whereas in many women the regularity of the menstrual rhythm is so precise that the flow recurs, not merely at regular intervals of twenty-eight days, but even time after time at exactly the same hour of the day—in other cases the interval between two periods may vary from twenty-one to thirty days.
L. Mayer, who made observations on the type of menstruation in 5,671 women, and tabulated his results, distinguishes between constant and inconstant intervals. Among the constant intervals he enumerates those forms, both regular and irregular, which do not during the whole life of the individual undergo transformation into another form, but remain always of the same type. If, for instance, in any individual the interval is always either two or eight weeks, in that woman menstruation is indeed irregular, but constant in type. If, however, for some years she menstruates at intervals either of two or of eight weeks, and then proceeds to menstruate at intervals of four weeks, her menstruation is of the inconstant type. Mayer found among his 5,671 cases
| The constant type in 4,981 women, that is in | 87.83 per cent. |
| The inconstant type in 690 women, that is in | 12.16 per cent. |
Of the cases in which the type was constant there were 69.68 per cent. in which the regular period of four weeks obtained, and 20.31 per cent. in which it was irregular in the sense above defined. Among these latter, the commonest periods were 15 to 21 days and 22 to 27 days. The same author observed the irregular type of menstruation in nearly one-fourth of the women belonging to the well-to-do classes.
According to the observations of Krieger on 481 cases in which the periods were regular, that is, in which the intervals in each case were equal in duration, the time from the commencement of one period to the commencement of the next was: