And without discussing the variations in the age limit of pregnancy , 55 years may be given as the age beyond which pregnancy does not occur .sx In the consideration of sexual capacity the physical condition and virility of the individual must not escape recognition , for , after all , it is not so much the age as the state of the organs and tissues that matters .sx Premature senility and excessive senility , i.e. , senility out of proportion to age , have their repercussion on sexual function , and this should not be overlooked in appraising the value of the medical evidence , notwithstanding the legal presumption that the generative power in the male does not disappear through age .sx And in these circumstances the value of an examination of the seminal fluid is obvious , for spermatozoa may be absent , few in number , inactive or dead , in contradistinction to the numerous actively motile spermatozoa found in the normal secretion .sx A convincing test is forth-coming when active sperms are found in the vagina or still more in the canal of the neck of the womb .sx The female secretions , in consequence of their chemical or bacterial content , may be inimical to the motility or to the life of the sperms .sx On the other hand , the female secretions may stimulate the sperms to renewed activity .sx These reactions are of importance in the study of female sterility .sx GENERAL DISEASES OR DISABILITIES IN RELATION .sx TO IMPOTENCE .sx Impotence may be due to endocrine disturbance , i.e. , a disturbance of the harmonious working of the endocrine or ductless glands .sx This disturbance may be present in association with sexual infantilism , where the sexual organs remain undeveloped or infantile , and it is the testicles , the pituary gland , the thyroid and the adrenals which seem to exhibit inadequate function .sx Yet minor disharmonies are much more frequent , which is amply borne out by the successful results obtained from glandular therapy .sx ' Impotence may result from certain general diseases , or from .sx what is loosely termed " general " , probably due to bacterial infection , but it may disappear with the cure or alleviation of the malady , and is therefore temporary in character .sx It is the permanent impotence resulting from disease which is of medico-legal significance .sx Diabetes is alleged to be an important cause of impotence , but this is only true of the advanced stages , and with our improved therapeutic methods the outlook in this disease has been completely changed .sx Chronic kidney disease and advanced pulmonary tuberculosis , also figure in the list of diseases alleged to be associated with sexual incapacity , at least in the advanced stages .sx And general debility from various causes is frequently brought forward as a cause for male impotence .sx Yet in all these disorders there is no justification for dogmatic statement , for in the matter of sexual capacity each individual is a law unto himself .sx And what is more , rapid recovery of sexual power is often a striking feature .sx Disease of Brain and Spinal Cord .sx Disturbances of the sexual reflex culminating in loss of sexual desire and loss of sexual power may be met with in certain diseases of the brain and spinal cord , and in traumatic neurosis due to injury or accident of which " Railway Spine " is an example .sx All these may become the subject of inquiry in the Law Courts .sx Loss of sexual desire and power may be an early symptom in locomotor ataxy , although it is generally present in advanced disease .sx Occasionally , in the early stages , desire increases while power diminishes .sx Exceptionally , however , desire and power are both increased in the early stages .sx Paroxysms of exaggerated sexual power and desire may be followed by periods of loss of power .sx A somewhat similar degree of sexual disturbance is found in the early stages of general paralysis of the insane .sx The great group of traumatic neuroses is important in forensic medicine , because of the frequency with which claims are made for the injury sustained .sx And it is noteworthy that nerve symptoms may develop weeks or months after the injury or accident , which serves to emphasize the necessity of settling claims without delay , for the outlook as regards recovery insuch cases is generally unfavourable .sx The men who suffered from " shell shock " in the Great War were sometimes found to be impotent .sx But with recovering health sexual power returned in , I believe , the vast majority , although in a few which have come under my immediate notice , the impotence remained .sx From the foregoing it is obvious that caution must be exercised in stating that permanent and irremediable impotence exists , for even in hemiplegia the general recovery may be so complete that sexual power remains unaffected , and it is only where the paralysis is extensive , as , for example , in ataxic paraplegia that impotence persists .sx Hence it follows that in paternity cases convincing medical evidence must be forthcoming to refute the contention that because of some cerebro-spinal disease the alleged father was incapable of begetting a child .sx Conception , pregnancy and parturition are unaffected in spinal paraplegia and even in the advanced stages of locomotor ataxy .sx There is thus a marked contrast in the effect produced by these diseases in the two sexes , and even childbirth is often easy and is generally painless .sx Priapism or persistent erection must not be regarded as a sign of potency !sx It may persist for some weeks , and it is both painful and difficult to relieve .sx Priapism may be a result of enlargement of the prostate gland and the cause of various acts of indecency .sx It is some-times a sequel of concussion and of injuries to the cervical spine associated with paralysis .sx Obesity .sx The relation of obesity to sexual capacity is well known not only in the consideration of human fertility , but also of animal fertility .sx Obesity or fatness may be the cause or the consequence of impotence .sx And it is well known that stallions put to stud that have grown fat are viewed with suspicion , and are not regarded as sure " getters" .sx The same is true of the genus homo , and the man after 40 years of age who waxes unduly fat suffers a corresponding .sx inefficiency in his sexual capacity .sx This is explained by disturbed testicular and/or pituitary secretion .sx But here , again , no general statement can be made , least of all a statement regarding sexual capacity which would carry weight in the Courts .sx Nevertheless , these individuals are often impotent , yet they may recover when their weight is reduced , and thus a statement to the effect that their impotence is permanent cannot be justified .sx Alcohol .sx The effect of alcohol depends entirely on the quantity imbibed and the duration of the alcoholic habit .sx In smaller doses alcohol is credited with exciting desire and increasing potency , while the larger doses impair potency .sx Where profound changes in the tissues have been produced by alcohol , permanent impotence may result , for the production of sperms is hindered .sx Excessive smoking is stated to be a further cause of impotence , as well as addiction to morphia and cocaine .sx But the effect of these poisons is dependent on so many factors , such as dosage , duration of administration , reaction of the patient , and so on , that due consideration must be given to each one in arriving at a decision .sx And in any case the discontinuance of the drug with the consequent improvement in health may be the means of restoring sexual power .sx Gonorrhoea .sx Although the sequelae of gonorrhoeal infection in the male do not as a rule interfere with the potentia coeundi , yet gonorrhoea is the great cause of generative incapacity .sx The ejaculatory ducts may become blocked , the posterior urethra strictured , and the semen prevented from flowing into the urethra .sx In these circumstances erection , muscular contractions to facilitate ejaculation , and orgasm are possible , but there is no seminal emission .sx After the penis has relaxed a few drops of fluid may escape when the hindrance is not complete .sx Moreover , double testicular disease may have destroyed spermatogenesis , i.e. , the production of spermatozoa , and as the secretion of the normal prostate is supposed to possess the power of activating spermatozoa , when the secretion and thatof the seminal vesicles is morbid , spermatozoa are rendered immobile .sx The production of spermatozoa may be further affected by disease , debility , or old age .sx Erectile power may continue for a considerable time after castration , i.e. , the removal of the testicles , for this operation does not interfere , at least for a time , with the reflex action culminating in erection .sx And moreover the principal function of the testicle is the production of spermatozoa , while the absence of the internal secretion ascribed to it , gradually produces an effect on the individual .sx The action of radium , X-rays , and mesothorium on the testicles has also led to the production of sterility where adequate measures had not been taken to protect these organs .sx Deficient Ejaculation .sx Deficient or even absent ejaculation may result from shock , emotion , sexual neurasthenia , or excessive indulgence , despite the retention of erectile power and the stimulus from friction .sx And the continued practice of coitus interruptus , amongst other deleterious physical effects , conduces to upset the ejaculatory mechanism .sx NULLITY AND PATERNITY .sx Impotence is the plea brought forward chiefly in Nullity and Paternity cases .sx And the question to be decided in a Nullity suit is , whether the husband or the wife is incapable of consummating the marriage .sx Now mere refusal to consummate is not in itself sufficient ; it must be persistent .sx Further , assuming there is incapacity , did the incapacity exist at the time of marriage ?sx Is it remediable ?sx Has any attempt at remedy been made ?sx Again , the completeness of sexual congress is becoming more and more recognized , although even a rudimentary vagina into which penetration is possible is sufficient to satisfy the law , although the remaining generative organs of the woman may be rudimentary or even absent , for the primary object of marriage , procreation , is entirely ignored .sx Nevertheless , a wider and Wiser interpretation of the law has been forthcoming in recent years , and where developmental defects of such a character as to interfere with satisfactory copulation are proved to exist , a .sx decree of nullity has been granted .sx But in this regard the female possesses the advantage in that the essential organs of generation are hidden within her body , whereas the corresponding organs in the male may be readily inspected on the surface .sx And the frequency with which the nullity suit is brought by the female has given rise to an impression among the laity that impotence is the peculiar property of the male .sx But the amount of defective development of the female sexual organs is probably far in excess of that in the male ( although comparative figures are not available ) , while the amount of acquired defect through disease and surgical operations is prodigious .sx Examples of acquired defect would come before the Courts in increasing numbers if the female organs were on the surface , but unless the defect is discovered or the condition of the vagina or front passage is such as to interfere with copulation the male remains in complete ignorance , assuming that he has not been informed prior to marriage , either that a mutilating operation had been performed or of the presence of disease .sx It is clearly the duty of every woman who has undergone an operation that interferes with her sexual capacity and who is contemplating marriage , to inform her intended husband of the nature of the operation , for it is not only right that he should know , but it may prevent a subsequent nullity suit .sx Needless to say numbers of women marry who have under-gone mutilating operations and who never tell either before or after marriage until perchance the conjugal fraud is discovered by a doctor , and not even then if the doctor remain silent .sx And it is a nice point of medical ethics to determine what should be the attitude of the doctor in these circumstances .sx Should he tell ?sx Again should he tell when he discovers well marked developmental defect unknown both to the husband and to the wife ?sx A short vagina with absent or rudimentary internal genital organs or varying degrees of developmental defect may never become known unless revealed by examination .sx