1132 THE REPRODUCTIVE ORGANS 



means, because neutral fat is readily demonstrable in the corpus luteum 

 of menstruation. 



Menstruation. — The process of menstruation is a periodic change 

 in the life cycle of the female which is most plastically betrayed by a 

 discharge of blood from the genitals, derived chiefly from the mucous 

 membrane of the uterus. In general, it may be said that this phenome- 

 non appears for the first time at puberty and is continued thereafter 

 at intervals of 28 days until about the forty-fifth year. This statement 

 would imply that it begins in temperate climates at about the twelfth 

 year and in cold climates at about the fifteenth year, but much depends 

 upon the physical condition of the individual as well as upon her sexual 

 development and mode of life. Thus, we are reminded at this time 

 of the child-woman of certain sections of India, where menstrua- 

 tion is regarded as a disgrace and where corresponding measures are 

 taken to prevent it with not especially flattering results to the off- 

 spring nor to the mother. In fact, Haller mentions a case of a child- 

 mother who menstruated regularly from her second year and gave birth 

 to a child at the age of nine. 



Before the first menstrual period, the approaching sexual maturity 

 betrays itself by a more rapid growth. The pelvis assumes a typically 

 feminine shape, the mammae become enlarged and hair begins to grow 

 upon the genitals as well as in the axillae. Although prone to be irregu- 

 lar at first, the menses are repeated as a rule every 28 days, 

 but certain variations in this time are by no means uncommon. The 

 hemorrhagic discharge sets in slowly, reaches a maximum about the 

 second or third day, and then gradually subsides. Consequently, not 

 more than 4 or 5 days are usually consumed by it. In our 

 country, menstruation ceases at about the forty-fifth year, but it has 

 been noted to disappear as early as the twenty-eighth year and as late 

 as the sixty-third year. It is by no means a rare occurrence that 

 women of fifty and over bear children. The cessation of the menstrual 

 flow is the expression of a series of changes constituting the menopause. 

 Underlying these changes are a series of important metabolic altera- 

 tions, the completion of which often requires several years and renders 

 the woman particularly susceptible to pathological processes of all 

 kinds. During the period intervening between puberty and the meno- 

 pause, conception may take place at any time. In rare instances, 

 however, this result has also been known to have been attained long 

 before sexual maturity as exemplified by the changes just enumerated. 

 Menstruation ceases immediately upon conception and does not recur 

 until after the termination of the periods of pregnancy and lactation.^ 



The discharge of blood, however, does not actually constitute the 

 menstrual period. It really begins several days beforehand, and is 

 ushered in by a feeHng of fatigue, pains in the back, headache, an 

 increased irritability of the nervous system, an unusual tenseness and 

 sensitiveness of the mammae, a congestion of the vulva, and a more 

 1 Ploss, Das Weib in der Natur und Volkerkunde, Leipzig, 1894. 



