OVULATION AND MENSTRUATION. 607 



occurrences may either precede or follow each other within certain 

 limits, and impregnation may still take place ; but the precise extent 

 of these limits is undetermined, and is probably more or less variable 

 in different individuals. 



Lastly, there are exceptional cases in which fertility exists without 

 a menstrual flow, and menstruation without ovulation. If we regard 

 the rupture of an ovarian follicle and hemorrhage from the uterus, in 

 menstruation, as two phenomena normally coincident, excited by a 

 common cause, and subservient to the same general function, we must 

 still recognize the possibility of either one being deranged indepen- 

 dently of the other. Various authors (Churchill, Reid, Yelpeau) have 

 related instances of fruitful women in whom the menses were scanty 

 and irregular, or even absent. The menstrual flow is habitually scanty 

 in some individuals, and abundant in others. Such variations depend 

 on the vascular activity of the system at large, or of the uterine organs 

 in particular ; and though the bloody discharge is usually an index 

 of the aptitude of these organs for impregnation, it is not invariably 

 so. Provided a mature egg be discharged from the ovary, pregnancy 

 is possible although the menstrual flow be absent. 



On the other hand we have met with a fully authenticated instance* 

 in which menstruation recurred regularly for several months without 

 the rupture of a Graafian follicle ; and twelve cases have been collected 

 by Goodman f in which menstruation continued notwithstanding the 

 removal of both ovaries, in the adult, by ovariotomy. But where the 

 ovaries are congenitally undeveloped, menstruation is also absent, and 

 the sexual system inactive. 



The blood which escapes during the menstrual flow is supplied by 

 the uterine mucous membrane. After death during menstruation, the 

 internal surface of the uterus is found smeared with a sanguineous 

 fluid, which may be traced through the uterine cervix into the vagina. 

 The Fallopian tubes are sometimes congested, and filled with a similar 

 bloody discharge. The menstrual blood has also been seen to exude 

 from the uterine orifice in cases of procidentia uteri, as well as in the 

 normal condition by examination with the speculum. It is discharged 

 by a kind of capillary hemorrhage, and, as a rule, does not form a 

 visible coagulum, owing to its being exuded from many minute points, 

 and mingled with mucus. When poured out more rapidly and abun- 

 dantly, as in menorrhagia, it coagulates in the same manner as blood 

 from other sources. Its discharge is, at the same time, the conse- 

 quence and the natural termination of the uterine congestion. 



* Transactions of the American Gynaecological Society. Boston, 1878, vol. ii., 

 p. 136. 



f Blchmond and Louisville Medical Journal, December, 1875. 



