l/ VI- MITTELSCHMERZ. By J. Halliday Croom, M.D., F. R.C.P. Ed., F.R.S.E., Physician to the Royal Maternity Hospital; Physician to, and Clinical Lecturer on Diseases of Women, Royal Infirmary; Lecturer on Midwifery and Diseases of Women, School of Medicine, Edinburgh.

(Communicated by Dr Haultain.)

I DO not propose to enter into a general discussion of dysmenorrhea. The object of the present communication is to discuss a form of dysmenorrhea, by courtesy so called, which occurs, not at the period when the external manifestation of men- struation takes place, but at mid-term,?a condition to which the " Germans have given an appropriate name, Mittelschmerz," and " which the French have, less felicitously, called Dysmenorrh^e intermenstruelle." Whatever name may be applied to it?and certainly intermenstrual dysmenorrhea is not suitable?the con- dition is a well-marked one, wherein an attack of dysmenorrhea proper is simulated, without, necessarily, any external haemorrhage. It does not at all resemble the pre-menstrual pain, or the continued pain associated with inflamed or diseased ovaries, but it is a con- dition which occurs definitely each month, at a definite period, and for a definite number of days. So far as I am aware, the condition was first of all described by MITTELSCHMERZ, BY DR J. HALLIDAY CROOM. 27

Sir William Priestly many years ago, and it has been also dis- cussed by Fasbender and Sorel. I will now recount the more important points of a case occur- ring in my own experience, which may be taken as fairly typical. It was that of a young girl of 18 years of age, whom I first saw at Prof. Simpson's private clinique somewhere about the year 1873. She complained of acute pain, sometimes in one side and sometimes in the other, occurring with the utmost regularity, fourteen or fifteen days after her menstruation. This had been the case ever since she was 14, and she did not begin to menstruate until she was 16. There was no abnormality, so far as I could discover, in the ovaries, tubes, or uterus. I saw her more or less regularly for thirteen or fourteen years after she first came under my observation. During all that time she menstruated with regularity, and her intermenstrual sufferings continued. During the years I knew her she occupied various situations in the capacity of a housemaid. She menstruated regularly and without pain, but every month she was obliged, in order to avoid her intermenstrual suffering, to use morphia rather freely. She ultimately married and went to the Colonies, and I know nothing of her subsequent history. Her pain began after a very severe attack of scarlet fever when she was about 14 years old. The second striking case that has come under my personal observation was that of a woman who was sent to my ward for profuse haemorrhage, associated with marked dysmenorrhcea, in addition to a definite and severe pain occurring between the men- strual periods, about the fifteenth day. The pain was severe and localised to the left side, and accompanied occasionally, though not always, by a slight discharge, sometimes of blood, and sometimes of clear fluid. On examination she was found to have a uterus enlarged to 3^ inches, and containing a submucous fibroid on the right side. After continued treatment, including curetting, she was sent home, but returned in a few months with the symptoms all con- siderably aggravated. It was resolved, therefore, with a view to checking the haemorrhage, which had become so profuse as to prevent the patient continuing her duties, to remove her append- ages. This was done; the right ovary was somewhat cystic and the tube thickened; on the left side the ovary was normal, but there was a well-marked hydrosalpinx. It is worthy of note, as bearing directly upon the case, that the woman was 35 years of age, and she had suffered from intermenstrual pain only for five years. It will therefore be seen that this case differed entirely from the last one, in which the condition of intermenstrual pain had existed from childhood. Two things, consequently, are clear about this case,?first, that the condition was distinctly an acquired one. Were it due to some condition of the ovary, then the Mittelschmerz should have 28 MlTTELSCflMEKZ, BY DR J. HALLIDaY CHOOM. been on the right side, whereas the pain was on the left, where the ovary was normal. Secondly, if it were due to painful ovulation occurring independently of menstruation, then it would have been expected that the intermenstrual pain would not have been of such recent origin. It is therefore by no means unlikely that this rare condition may be due to the over-distension of the Fallopian tube with fluid, and that the pain of the Mittelschmerz is associated with its expulsion. This question of hydrops tubse profluens I shall discuss later on. Case 3.?A woman, 25 years of age, was brought to St Luke's Home some years ago suffering from severe dysmenorrhcea, the dysmenorrhcea occurring for the first three days of the menstrual period. Various remedies were prescribed, but she returned to the Home some months afterwards, being no better. A local examina- tion was then made, when it was found that the uterus was some- what enlarged and acutely retroflexed. The condition of the appendages was apparently normal. During her stay in the Home, which was rather protracted, and before any operative interference had been undertaken, my atten- tion was drawn to her having acute suffering in the left side, about fifteen days after menstruation, very similar to the pain she suffered at her menstrual period, but not so severe. I examined her then, and found the condition in the pelvis as I have described, with the addition that there was a distinct fulness at the left side, the nature of which, at the time, I did not recognise. On further inquiry, I found that she had had this mid-term pain, lasting for a few hours, regularly for four or five years. With a view to curing her dysmenorrhcea the cervix uteri was dilated, and she was sent off in the hope that her dysmenorrhcea would be relieved. Months later she was brought back again by her mistress, who said she was quite unfit for her duties as a servant, and must therefore, unless cured, leave her situation, all the more so as twice in the month she was temporarily hors die combat. I am not perfectly sure what the further treatment was which she underwent for her dysmenorrhcea, but, whatever it was, it was unavailing. The case was brought to me after I came to be in charge of beds in the Infirmary, and after carefully considering the matter with the doctor in whose charge the patient had been, I somewhat unwillingly removed the ovaries. I found that there was well- marked hydrosalpinx of the left tube. The fact that this condition of the hydrosalpinx, of the size of a small hen's egg, was not found except on the one occasion referred to above, led me to the con- clusion that it was one of those cases of hydrops tubae profluens, and this conclusion was entirely supported by the subsequent history of the case; because, although the removal of her ovaries and tubes neither stopped her menstruation nor cured the dys- MlTTEiiSOHME HZ, BY DR J. HALL1DAY CKOOM. 29 menorrhcea, the intermenstrual pain did not recur for at least a year afterwards, since which time I have not heard of the case again. The four cases recorded by Priestly in the British Medical Journal for 1872, which appear to be the earliest recorded cases presenting this condition, have the following as their prominent features:?Pain, paroxysmal, in the region of the ovary, occurring during the intermenstrual period ; in some cases continuing up to the commencement of the flow, in others stopping before then. The ordinary flow is usually scanty, but regular, and with no pain. On Bimanual Examination.?In two cases tumour felt in region of broad ligament, adherent to uterus, elastic to touch. In the other two cases only thickening in the region of the broad ligament. Sorel records a case, presenting symptoms similar to those mentioned above, in which the condition existed for a great number of years; indeed, observation had been made during a period in which 147 menstrual epochs had occurred. The chief conclusion arrived at by this author was that the occurrence of the intermenstrual pain bore a more definite relation to the com- mencement of the period which followed it than to the period which went before, as there always elapsed fourteen days between .the occurrence of the pain and the commencement of the menstrual period. One of the most important contributions to the very limited literature of this subject is an article by Heinrich Fasbender, pub- lished in 1876, in the Zeitschrift fur Geburtshiilfe und Frauen- JcranJcheiten. The case, which he quotes as having occurred in his own experience, presents the following features :? An unmarried woman of 24, anaemic, with an anxious cast of countenance, had menstruated regularly since her fourteenth year. The flow was always sparing, and for a few days before its appear- ance there was a severe pain in the lower part of her abdomen, with gastric disorder, cachexia, and alternate sensations of heat and cold. For the past two years there had occurred, at the four- teenth to sixteenth day after menstruation, a disorder similar to that which accompanied the ordinary menstrual period, accom- panied by a flow of mucus from the vagina so conspicuous as to have caused her to mention it without its being suggested to her. Her nervous system had become much affected by the pain and discomfort which she underwent, so much so as to have produced symptoms of hysteria and a mental condition bordering on melancholia. Physical examination showed the presence of an acute ante- flexion of the uterus, with chronic endometritis and colpitis, with lesions of the os. Nothing abnormal was found in the uterine annexa. On seeing her again at the time of her intermenstrual pain, he came to the conclusion that the mucous discharge was most 30 MITTELSCHMERZ, BY DR J. HALLIDAY CROOM. copious when the feeling of heaviness in the pelvis was most marked, pointing to a congestion in the pelvic organs. Fasbender's view of the etiology of Mittelschmerz is that, accepting Pfliiger's theory of menstruation, we have in some cases a premature sum- mation of nervous stimuli in the ovary, with the occurrence of ovulation, caused either by a delicately organised and excitable state of the whole nervous system or of the nerves of the ovary, the latter state produced by a pathological condition of the ovary. This abnormal irritability leading to dehiscence of a follicle, some fourteen days before the proper menstrual period, produces the congestive condition of the pelvic organs found in cases examined at such a time. In the discussion which followed the reading of Herr Fas- bender's paper several additional cases were cited and opinions expressed. Two gentlemen cited cases where the intermenstrual pain had occurred in women suffering from anteflexion of the uterus; and a third suggested the anteflexion as the cause of the Mittelschmerz, the pain being due to contraction of the uterus, trying to expel retained blood, etc. To this it was replied that in the observed cases no contractions of the uterus could be discovered, and further, anteflexion was not present in all cases of Mittelschmerz, while if it were caused by anteflexion, Mittelschmerz would be a much commoner symptom than it is. Mittelschmerz with a slight flow of blood is also described by Herr Benicke as occurring in a case where there was a conical cervix with pinhole os, anteflexion of the uterus, and retraction of the utero-sacral ligament. From the above notes, which, so far as I can discover, include a mention of nearly every case of Mittelschmerz which has been recorded, the condition, it seems to me, can be well considered as having three different manifestations. 1. A group of cases in which there is no external manifestation at all. 2. Those cases where the pain is associated with an escape of blood. 3. Those in which, as in two of my cases and some of the others, the intermenstrual pain is associated with a clear discharge. It would be absurd to dogmatize upon the causes which give rise to this condition, or to lay down any hard and fast rules as to the pathological conditions necessary to its production, but it seems to me that the above classification gives a fair insight into the different states that may lead to the production of this somewhat unusual symptom. (1.) With regard to those cases where no external manifestation accompanies the occurrence of Mittelschmerz, the explanation is probably to be found in the fact that ovulation and menstruation do not in these cases occur simultaneously; that, in addition, MITTELSCHMERZ, BY DR J. HALLIDAY CROOM. 31

owing to thickening of the capsule of the ovary, or some such cause, dehiscence of the follicle occurs with pain. (2.) Those associated with escape of blood. In all of these it will be observed that there was present more or less endometritis, anteflexion, and enlargement of the uterus, and, so far as I am able to judge, these were simply cases in which a slight intermenstrual flow, due to endometritis, was accompanied by well-marked pain during the passage of clots. Such a condition is well recognised and common, and scarcely, I think, should come under the category of Mittelschmerz at all. Still, it adequately enough describes a set of cases to which the Germans especially have drawn attention. Lastly, with regard to those cases in which a leucorrhoeal dis- charge is described as occurring with the Mittelschmerz, and where, just before the usual date of the occurrence of the pain, a swollen and fluctuating condition of the tubes was in some cases made out, I think there can be no question that the cause of the intermenstrual pain was to be found in hydrops Fallopii, reaching its full development at mid-term. I am well aware that much doubt is now thrown upon the pos- " sibility of the existence of what is called intermitting hydro- " " salpinx or hydrops tubse profluens," the occasional sudden escape of fluid through a temporarily patent uterine end, with disappearance and diminution in size of the tubal dilatation. According to some, it is much more likely that these discharges pass, not through the cervix, but by a vaginal fistula communi- cating with the cyst. Either explanation is compatible with this view of mine. In my case, in which a removal of the tubes and ovaries brought about a cessation of the Mittelschmerz, it may be urged that the pain had been ovarian, and that the removal of the hydrops did not lead to its cessation, but the removal of the ovary. Here I would remind you that colicky pain in the tubes in such a con- dition occurs, contractions of the sac forcing the fluid through a uterine orifice only partially closed; and also that pain may be due to discharge of uterine contents, the result of reflex contraction of a necessarily congested uterus. Thus it is more than likely that the pain was really tubal.

Prof. Simpson agreed with the President in regarding this as an able and very interesting communication. That the literature on this subject was scanty was probably due to the circumstance that the patients who suffered from intermediate pains usually suffered also from other pelvic distress, so that the special symptom did not receive special attention. Dr Croom had done a good service in directing attention to it and in relating such instructive cases. He (Prof. Simpson) believed that Dr Croom was correct in attributing the symptoms to tubal distension, which, 32 MITTELSCHMERZ, BY DR J. HALLIDAY CROOM. however, was very apt to be associated with ovarian inflammation; and in cases that had come under his observation the measures that had been serviceable in dealing with salpingo-oophoritis had succeeded in relieving this symptom also. Dr Milne Murray agreed with Professor Simpson as to the interest of Dr Croom's paper. He was also at one with him as to " the comparative frequency of these cases of middle pain." He had met with several in his practice. One of the earliest he had observed was that of a young unmarried lady who had been a patient of Dr "W. L. Eeid of Glasgow. Dr Eeid had treated her for an attack of endometritis with enlargement of the uterus and retroversion. When she came under Dr Murray's observation the endometritis was almost cured, and she was wearing a pessary. She then complained chiefly of what she herself termed her "middle pain," which came on exactly fourteen days after the commencement of her period. The pain was intense, referred sometimes to one side, sometimes to the other, and was associated with great headache and prostration. It was most acute on the second day, and generally ceased suddenly. The only relief she obtained was by the use of very large doses of bromide of potash, which induced a sort of stupor. In this case nothing abnormal could be found in either tubes or ovaries,?the latter being not more sensitive than usual. At the time of the pain they were, however, very sensitive on examination. The steady use of the hot douche seemed to diminish the suffering considerably after some months. Some time after this her endometritic symptoms were aggravated by the effects of exposure to wet and cold, and she began to suffer from great dysmenorrhea, and after simple remedies had been exhausted, the cervix was dilated, the cavity curetted and cauterised. This quite relieved the dysmenorrhcea, " " but the middle pain still continues, though on the whole it is less severe than at first. Another case which he saw recently is of more physiological interest. The patient is a married lady 32 years of age, and the mother of four children. Her periods are quite normal, both as to amount, sensation, and regularity, but on the fourteenth day after their commencement she is seized with a violent pain in the lower part of the abdomen, which lasts always for two, sometimes for three days. She is compelled to lie down for a part of the time. The pain generally ceases suddenly. She experienced this before her marriage for three or four years at least. On examination the pelvis seems quite normal in every way. A point of special interest is that all her four children have been born a fortnight before the calculated time, and she states that the only time she experiences sexual pleasure is for a day or two after the pain ceases, this being quite absent at all other times. Dr Murray could not help thinking that this pain was connected in all cases with the process of ovulation. In the last case this seems strongly borne out; and even in the cases cited by Dr MITTELSCHMEEZ, BY DR J. HALLIDA.Y CROOM. 33

Croom, where there was evidence of tubal distension, it seems essential to postulate some recurring process such as ovulation to provide the nervous or muscular tension necessary to effect the evacuation of the tube. Without this it is difficult to see how the periodic discharge of the contents would be brought about. It seemed to him that the occurrence of ovulation at a period midway between the menstrual processes was sufficient to account for the pain both in those cases where a gross lesion could be detected, and also in those where no such condition could be determined. Dr J. W. Ballantyne thought a possible cause of severe inter- menstrual pain might in certain instances be found in the presence of a double uterus, one of whose horns was imperforate, for it was well known that in the bicornate and didelphic organ menstruation might occur once a fortnight, the blood coming from one cavity one fortnight, and from the other the next. If one of the uterine cavities did not communicate with the vagina, then there might be an intermenstrual pain without any visible haemorrhage. He did not quite agree with Dr Croom that it was best to adopt the German name for this condition. He thought that intermediate pain or dolor intermedius menstrualis were in some ways pre- ferable. Dr Haultain agreed with Dr Milne Murray in attributing the Mittelschmerz in the majority of instances to ovarian origin, and most probably to ovulation. Its marked periodicity was indica- tive of such an origin, and cases were by no means uncommon where periodic pain was complained of a few days before or after the period, which was to be accounted for on similar grounds. In fact, when ovulation or menstruation were not coincident in women suffering from inflamed and tender ovaries, such a condition must be expected. Dr James Ritchie felt much interest in Dr Croom's paper as helping to elucidate an obscure subject, and also because he had, in the cases which had come under his own observation, adopted a different theory to explain the phenomenon in question. Men- struation was due to a discharge of nerve energy towards the uterus and its appendages. There were evidences that this discharge might take place independently of ovarian activity. The cycle of menstruation was usually about twenty-eight days, but Dr James Ritchie believed that there was an intermediate discharge of nerve influence of variable degree, and that the middle pain was induced in that way by mechanism similar to that which produced it at the monthly time. His reasons for believing that this nerve dis- charge existed, and that it might be the primary cause of the pain, was derived from three considerations. 1. In certain abnormal conditions of the cervix there was a discharge of blood at the middle of the period. 2. That if labour did not set in at the tenth cycle calculated from the last period it was often delayed for fourteen days, and in some cases happened fourteen days before E 34 EXPERIMENTAL RESEARCH INTO THE ACTION OF the tenth cycle. 3. When a woman did not nurse, and even in some cases of subinvolution of the uterus while she was nursing, the catamenia reappeared six weeks after confinement.