670 



UTERUS AND ITS APPENDAGES 



state in animals, but is in many of its essential 

 features the direct converse of this. 



For, as already stated, in the mammalia 

 usually by the time that the ovum has reached 

 the uterine extremity of the oviduct, or has 

 entered the uterus, the opportunity for im- 

 pregnation is lost, the cestrus is over, and the 

 animal refuses the male : all the conditions 

 immediately necessary to procreation then pass 

 away, and an interval of perfect inaptitude en- 

 sues, which is sometimes so remarkable that 

 not only are no ripe ova to be found in the 

 ovaries, but even the male organ ceases to 

 secrete semen. In this series of recurrent 

 periods, marked by irresistible impulse, alter- 

 nating with total inappetence for congress, 

 nothing is more evident than that each corre- 

 sponds with an internal physical condition, of 

 which it affords a most intelligible explana- 

 tion. The appetency occurring and remain- 

 ing only as long as congress would be fruitful ; 

 the inappetency returning whenever this would 

 be necessarily infertile. 



Now, with regard to the human subject, 

 whatever may be possible during menstruation, 

 yet essentially the intervals of the menstrual 

 acts are the times of fertility in women. And 

 the only question that can arise upon this 

 point is, whether the power of conception ex- 

 tends over the whole or over a part only of 

 this interval a question that has been already 

 considered. 



In all that relates, therefore, to the coinci- 

 dence of the ovipont with the oestrus of mam- 

 mals, the evidence derived from comparative 

 anatomy serves to strengthen the belief in a 

 corresponding correlation between the emis- 

 sion of ova and the act of menstruation in the 

 human subject. But in respect of the inter- 

 val, the great divergence of the facts here dis- 

 played tends to embarrass and perplex rather 

 than to elucidate the question as it relates to 

 man. For it is precisely in this interval that 

 all the circumstances occur which, for want of 

 a consistent explanation, have often thrown a 

 doubt over the whole theory of the direct 

 dependence of menstruation upon ovarian in- 

 fluence ; and in elucidating these points, com- 

 parative anatomy affords little or no help. 



In taking a retrospect of these several facts 

 relating to menstruation and its connection 

 with a corresponding ovipont, an essential 

 distinction should be made between the influ- 

 ence of the ovaries in determining the power 

 of the uterus to perform the menstrual act, 

 and any influence which they may have over 

 the periodicity of that function. In all that 

 relates to the former faculty, the power of the 

 ovaries may be regarded as indisputably esta- 

 blished. In much that is connected with the 

 latter, there is obviously room for more in- 

 formation than we at present possess. 



If each separate act of menstruation is de- 

 termined by certain modifications periodically 

 occurring in the ovary, it is probable that the 

 essential part of the process is the maturation 

 of an ovum within the follicle, while the 

 process of its emission may be an accidental 

 feature, not always occurring, sometimes hap- 



pening spontaneously, and sometimes caused 

 in the way already suggested, but having 

 nothing necessarily to do with the menstrual 

 act, although the time of its occurrence may 

 materially affect the period of a resulting im- 

 pregnation. 



The purpose of the^/ftu- remains to be con- 

 sidered. If the quantity of fluid escaping at 

 each recurrence of menstruation be estimated 

 at three, or possibly five, ounces, and the pro- 

 cess is repeated, without interruption from 

 pregnancy, lactation, or disease, once in every 

 lunar month, or thirteen times annually for 

 thirty years, then an aggregate quantity of 

 seventy-two pounds or nine gallons on the for- 

 mer supposition, or of a hundred and twenty- 

 two pounds or fifteen gallons upon the latter 

 estimate, will have passed from the system in 

 the course of menstrual life, and, so far as 

 this is composed of blood, will have been ap- 

 parently entirely wasted. 



It is difficult to arrive at a perfectly satis- 

 factory conclusion regarding the purpose of 

 this large loss. For the external escape of 

 blood must be regarded as, to a certain ex- 

 tent, an accidental feature in the process of 

 menstruation. That it is not essential to fer- 

 tility, is proved by the fact that women some- 

 times, though very rarely, breed who do not 

 menstruate ; that the temporary suspension of 

 the menstrual flow during lactation is no cer- 

 tain preventive of conception ; and that, oc- 

 casionally, young girls become pregnant before 

 the menstrual age has arrived. 



The blood which escapes is certainly con- 

 verted to no positive use. No office can be 

 assigned to it, such, for example, as has been 

 suggested for the analogous escape of blood 

 into the ripe ovisac an effusion that has 

 been termed the menstruation of the follicle.* 

 But although the blood, after it has passed 

 the uterine epithelium, is altogether lost, it 

 may, by escaping, fulfil the negative purpose 

 of affording relief to the congested capillaries 

 of the uterus. For we find, from various kinds 

 of evidence, that, at each menstrual period, 

 all the uterine tissues become charged with a 

 more than ordinary quantity of blood, ami, 

 therefore, with the materials necessary to 

 those rapid growths which have been shown 

 to commence as soon as impregnation has 

 taken place. From the moment that the 

 latter occurs, the mucous and other tissues 

 of the uterus begin rapidly to expand, and 

 the current of blood is diverted to new chan- 

 nels. There is then no overplus, until the 

 whole cycle of generative acts, including lacta- 

 tion, is complete. The only observable break 

 happens at parturition ; but after the balance 

 of the uterine circulation has been restored 

 by the escape of blood at the time of labour, 

 and by the lochia, there is again usually no 

 redundance until the office of the mammary 

 glands has ceased. Then, the activity of the 

 ovaries recommencing, the periodical hyper- 

 aemia of the uterine vessels returns, and the 

 overplus is emitted in the form of menstrual 



* See p. 556. 



