MENSTRUATION. 709 



During infancy and childhood the sexual system is inactive. No dis- 

 charge of eggs takes place from the ovaries, and no external phenomena 

 show themselves, connected with the reproductive function. 



But at the age of fourteen or fifteen years, a change begins to mani- 

 fest itself. The limbs become rounder, the breasts increase in size, and 

 the entire aspect undergoes a peculiar alteration, which indicates ap- 

 proaching maturity. At the same time a discharge of blood takes place 

 from the generative passages, accompanied by some disturbance of the 

 general system, and the female is then known to have arrived at the 

 period of puberty. 



Afterward, the bloody discharge returns at regular intervals of four 

 weeks ; and, on account of this recurrence, corresponding with succes- 

 sive lunar months, its phenomena are designated by the name of the 

 " menses" or the " menstrual periods." The menses return with regu- 

 larity, from the time of their first appearance, until the age of about 

 forty-five years. During this period, the female is capable of bearing 

 children, and sexual intercourse is liable to be followed by pregnanc}'. 

 After the forty-fifth year, the periods first become irregular, and then 

 cease altogether ; and their final disappearance is an indication that 

 pregnancy cannot again take place. 



During the period above referred to, from the age of fifteen to forty- 

 five years, the regularity and completeness of the menstrual periods 

 indicate to a great extent the aptitude of individual females for im- 

 pregnation. All causes of ill health which derange menstruation are 

 apt at the same time to interfere with pregnancy ; so that women whose 

 menses are regular and natural are more likely to become pregnant, 

 after sexual intercourse, than those in whom the periods are absent or 

 irregular. 



Jf pregnancy happen to take place, however, at any time within the 

 normal period, the menses are suspended during its continuance. They 

 usually remain absent, after delivery, until the end of lactation, when 

 the}' recommence, and continue to recur at their regular periods, as 

 before. 



The menstrual discharge consists of mucus mingled with blood. 

 When the period is about to come on, the female is affected with a 

 certain degree of discomfort and lassitude, a sense of weight in the 

 pelvis, and more or less disinclination to society. These symptoms 

 are in some instances slightly pronounced, in others more troublesome. 

 An unusual discharge of vaginal mucus then begins to take place, soon 

 becoming yellowish or rusty brown in color, from the admixture of a 

 certain proportion of blood ; and by the second or third day the dis- 

 charge has the appearance of nearly pure blood. The unpleasant sen- 

 sations, at first manifest, then usually subside ; and the discharge, after 

 continuing for two or three days longer, grows more scanty. Its color 

 changes from red to a brownish or rusty tinge, until it finally disap- 

 pears altogether, and the period comes to an end. 



The menstrual epochs of the human female correspond with the 



