Part 24

As a result of anatomical investigations, Négrier, in 1840, was the first to establish the thesis that in women suffering from congenital absence of the ovaries, menstruation never occurs; that after the loss of the ovaries, menstruation always ceases; that during pregnancy and lactation and during the climacteric period, ovulation ceases; and that a relation of temporal succession obtains between ovulation and menstruation. This close relation between the two processes was maintained also by Gendrin at about the same date. Later, Girdwood, by post mortem research, proved that the number of scars in the ovary coincides with the number of previous menstruations.

Brierre de Boismont, in his exhaustive work on Menstruation, lays stress on the view that the periodically recurring ovulation furnishes the impulse for the menstrual flow. First among German investigators, Bischoff upheld the opinion that maturation and discharge of ova are spontaneous processes occurring independently of sexual intercourse, and compared heat or rut in other animals to menstruation in women—a view shared by Pouchet and Coste. Ovulation occurs simultaneously with the menstrual flow, and the follicles burst toward the end of menstruation.

Pflüger, in his important work on the significance and cause of menstruation, has demonstrated the causal connection between menstruation and ovulation. The bleeding and the discharge of the ova are according to him joint effects of a common cause. It is not the bursting of the follicle, but the ripening of the follicle, that gives rise to the menstrual congestion. The pressure of the growing follicle on the surrounding ovarian tissue gives rise to a continued stimulation of the ovarian nerves; the summation of these stimuli, which after the lapse of a certain time attain always a certain degree of intensity, results in a reflex from the spinal cord taking the form of great congestion of the genital organs; this congestion leads, on the one hand, to hæmorrhage from the uterine mucous membrane, and, on the other hand, and as a rule simultaneously, to the bursting of the ovarian follicle. The swelling and granulation of the uterine mucous membrane at every menstrual period signifies nothing else than the commencement of the formation of the decidua.

Nägele already mentioned the view, that inasmuch as immediately after the first appearance of menstruation a woman has become capable of reproducing the species, each process of menstruation must be regarded as a renewal of the exhausted faculty for conception.

Pflüger’s teaching has been opposed by Sigismund, who, whilst admitting the periodicity of ovulation and menstruation, yet regards the two processes, in the uterus the formation of the menstrual decidua, in the ovary the rupture of the graafian follicle, as independent of one another, even though they occur simultaneously. Should fertilization occur, the ovum implants itself in the prepared soil; should fertilization fail to occur, the menstrual hæmorrhage ensues. Thus, the occurrence of menstruation indicates that fertilization of the ovum has failed to occur. On this theory, then, the ovum that is fertilized belongs to the first period missed, whereas Pflüger assumes that when pregnancy occurs, it is always the ovum belonging to the time of the previous menstruation—the last actual menstrual discharge—that is fertilized.

Löwenhardt, in his work on the Diagnosis and Duration of Pregnancy, advances the same views as Sigismund. The fertilized ovum, in his opinion also, is that of the first period missed; and since at the time at which he believes fertilization to occur the ovum is certainly still in the ovary, fertilization, on this theory, must always take place in the ovary itself, and the fertilized ovum cannot begin its intra-uterine life till a month has elapsed after fertilization. Reichert, Kundrat, Engelmann, and Williams, basing their views on anatomical data, are of opinion that ovulation recurs periodically, and that the extrusion of the ovum occurs not before but after the commencement of menstruation.

According to Hensen, the observed facts support the view that the follicles burst as a rule toward the end of menstruation; anticipation or postponement of the opening of the follicle (conception before or after menstruation) would, however, appear not to be impossible.

Leopold, who assumes that menstruation may occur without ovulation and ovulation without menstruation, maintains on anatomical grounds that the rupture of the graafian follicle occurs chiefly during menstruation, under the influence of the swelling due to menstrual congestion. Menstruation with ovulation he believes to be a common occurrence, menstruation without ovulation, an unusual occurrence. Further, it is certain that, at the time when the periodic bleeding is due, ovulation may occur, even though the menstrual discharge fails to make its appearance (ovulation without menstruation).

Chazan and Gläveke also adhere to the generally accepted view that ovulation is a periodic process, usually but not necessarily synchronous with menstruation.

Strassmann bases on clinical facts and on experiments the following view of the connection between ovulation and menstruation. The principal processes in the organism of the sexually mature woman run their course in a periodic rhythm resembling an undulatory movement, the acme of which occurs in the antemenstrual period with the aim of preparing for the development of an infantile organism. Whilst an ovum is maturing in the ovary, in the uterus, in dependence upon this maturation, the antemenstrual mucous membrane, fitted for the reception and nutrition of the fertilized ovum, is also undergoing development. At the acme of the undulatory movement, the graafian follicle ruptures and the ovum is liberated, to undergo fertilization in the infundibulum of the Fallopian tube. If fertilization fails to occur, or if for any reason the graafian follicle fails to rupture, then, in consequence of and at the time of the highest intra-ovarian tension, at the time, when the rupture of the follicle usually occurs, the extrusion of blood from the capillaries of the uterine mucous membrane begins. The intermediation between the ovary and the uterus is probably effected by means of the sympathetic ganglion in the ovary discovered by Elizabeth Winterhalter, and effected in this manner, that the stimulus proceeding from the ripening follicle passes along the nerve-fibrils surrounding the follicle to the processes of the nerve cells of this sympathetic ganglion, accumulating in these cells till a certain degree of intensity has been reached, and then, by means of other processes and of the vasomotor nerves, influencing the vessels of the uterus.

Gebhard likewise believes menstruation to be dependent on the ovarian function, and thinks that it is probably brought about in a reflex manner by the gradual growth of the ovarian follicles. It appears that most commonly at the time of menstruation a graafian follicle ripe to bursting is to be found in the ovary, but to this rule there are many exceptions. We cannot exclude the possibility, that the ovum from a follicle that burst after the commencement of the menstrual flow may be fertilized; but more commonly the ovum that is fertilized is that of the first period missed. The sudden decline in vital energy that occurs just before menstruation is explained by Gebhard as a kind of atavism, dependent on the fact that many of the lower animals, butterflies, for instance, succumb as soon as they have fulfilled their duty of reproducing the species.

A number of modern investigators, however, deny that any relation, temporal or causal, exists between ovulation and menstruation, and affirm that the latter process is quite independent of the former.

Thus, Christopher Martin maintains that a special menstrual centre exists in the lumbar portion of the spinal cord, the impulses from which proceed to the uterus by way of the splanchnic plexus, the ovarian plexus, or perhaps by both. Similar views are held by Lawson Tait, Collins, and Johnstone, who severally maintain that the ovaries are no more concerned in the production of menstruation than any other organ of the body—the liver, for instance. They direct attention to the periodicity that occurs in the functional activity of various other organs, in respiratory and cardiac activity, for instance, both of which undergo rhythmical changes as a result of nervous influences. The cessation of menstruation after oöphorectomy they attribute, not to the cessation of ovulation, but to the division of the nerves which run across the broad ligaments of the uterus and upon which menstruation depends. Heat and rut in animals have a different significance from menstruation. The latter process is induced by civilization and by the adoption of the upright posture.

But, taking all this into consideration, we must hold fast to the fundamental principles, that ovulation occurs at that period of life, and only at that period, during which menstruation proceeds regularly; that ovulation begins when externally and in the whole development of the girl the signs of sexual maturity manifest themselves; and that ovulation ceases at the climacteric, when menstruation also ceases. We must regard as rare exceptions to this rule cases in which ovulation begins before the menarche and persists after the menopause.

A physiological interruption of menstruation occurs during pregnancy and lactation; it seems improbable, however, that during this interval ovulation also is in abeyance. It is established by anatomical investigations that ovulation and menstruation commonly occur in association; but that menstruation sometimes, though rarely, occurs in the absence of ovulation; and, finally, that intermenstrual ovulation is also a rare occurrence. In the majority of cases, either just before or just after the commencement of the menstrual flow, rupture of a graafian follicle occurs. After complete oöphorectomy, menstruation ceases; it is only when functionally active portions of ovarian tissue have been left behind, that menstruation continues to occur. In the absence of the ovaries, the menstrual function is in abeyance; hence, for the performance of that function, the presence of ripening ovarian follicles and of other follicles capable of ripening later, is an indispensable requisite.

A certain analogy between heat and rut in animals and menstruation in women may, according to the investigations of Bischoff, Hegar, Strassmann, and others, certainly be maintained. Heat or rut is a process occurring in mammals, dependent on the reproductive glands, characterized by an increase in sexual and general excitability, with congestion of the pudendum and the vagina, swelling of the sebaceous glands of the external genitals, and increased secretion; from the vulval cleft there flows a peculiar, strong-smelling mucus, often tinted red from admixture with blood; there is frequent micturition, the uterine glands are swollen, the Fallopian tubes are also swollen, and are soft and erected. A well-developed menstrual bleeding, analogous to that which occurs in the human species, occurs, among the lower animals, only in apes. Maturation of ova precedes the period of heat, and rupture of the graafian follicle occurs during that period.

Heat or rut occurs in animals at certain seasons of the year, which may, according to the species and the mode of life of the animal concerned, be in spring, summer, autumn, or winter. The season of heat or rut has further several periods of heat, each lasting several days, and among domesticated animals, mares, cows, and bitches, succeeding one another at intervals of three or four weeks; in wild animals, rut occurs once only in the year. In animals, sexual intercourse takes place during the time of the menstrual discharge, and during this time also the capacity for conception is increased; in the absence of heat, the genital organs are in a more quiescent condition. In this connection, the experiments on animals made by Strassmann, with a view to determining the influence upon the uterus of rise of pressure in the ovary, are of great interest; these experiments showed that a rise of intra-ovarian pressure, produced by the injection of fluid into the parenchyma of the ovary, led to changes in the endometrium and the external genital organs corresponding to those occurring in an animal on heat.

In the human species, however, in contradistinction to what occurs in the lower animals, there is a certain disinclination, on the part of the male at any rate, to sexual intercourse during menstruation. The human female moreover, notwithstanding the periodicity of her sexual life, is at all times capable of conception; this capability is not confined to any particular part of the intermenstrual period, for conception may occur at any time during that period, and has even been known to result from intercourse during menstruation. This peculiar characteristic of the human reproductive capacity has been regarded as compensatory, furnished by nature in her continual endeavour for the perpetuation of the species, to counteract the restricting influences imposed by civilization on the normal process of reproduction.

Credible observations even exist, indicating that among many primitive peoples, in whom at the time of puberty no social laws hinder the limitless exercise of the reproductive functions, this capacity on the part of woman to conceive at any time has no existence, and that the reproductive capacity of such human beings is, like that of the lower animals, confined to a certain season of the year. Thus, G. Schlesinger reports of the Ainus of the island of Yezo, “A friend of mine in Sapporo believes himself to have observed that the Ainus have a certain definite rutting period, and that in them, as in many of the lower animals, the process of reproducing the species occurs only at a certain season of the year.” An identical statement is current concerning the Indians of Western America.

The mucous membrane of the uterus undergoes during menstruation important changes, and a question much disputed is, whether in the course of menstruation the whole of the uterine mucous membrane is removed, or a part only, whether it is shed in its entire thickness, or is at least deprived of its epithelium. According to the observations made by Leopold on dead bodies, the mucous membrane of the uterus becomes swollen shortly before the commencement of the menstrual discharge, until, partly in consequence of cellular proliferation, partly in consequence of œdematous infiltration, and partly in consequence of enlargement of the lymph-spaces, it attains a thickness of 6 to 7 millimetres (¼ of an inch). The superficial capillaries are notably enlarged, and an effusion of blood-elements continues for several days, without the occurrence of any fatty degeneration in the tissues. The epithelium and the most superficial cell-layers of the mucous membrane are, however, undermined and shed. No complete destruction of the mucous membrane occurs, however, and fatty degeneration forms no part of the menstrual process as such.

Möricke, who examined portions of the uterine mucous membrane removed with the curette during menstruation from living women, found the superficial layers of the mucous membrane to be intact, and he regards the shedding of the epithelium described by other authorities as cadaveric phenomenon. Sinéty, who also found the uterine mucous membrane intact during menstruation, adheres to the same view.

Von Kahlden concludes, as a result of investigations made post mortem, that during menstruation the greater part of the mucous membrane, not the superficial epithelium only, but the stroma itself down to its deepest layers, is shed. According to von Tassenbroek and Mendes le Leon, however, the most superficial layers only are shed during menstruation.

According to Westphalen, whose investigations were made, partly on masses removed by the curette, and partly on freshly extirpated uteri, a sanguineo-serous infiltration of the mucous membrane begins about ten days before menstruation. Great vascular dilatation occurs only just before menstruation. The uterine glands undergo enlargement, and during and immediately after the flow, numerous shed epithelium cells occupy the lumen of the glands. For the rest, however, in the interior of the uterus shortly after menstruation, we find an almost continuous epithelial covering. Some days after menstruation, the proper regeneration of the mucous membrane occurs.

Mandl, who examined totally extirpated uteri, asserts that during menstruation the epithelial covering of the mucous membrane is never completely lost, but that just as little does it remain completely intact. The regeneration of the lost areas of epithelium proceeds even during menstruation.

The researches of Kundrat and Engelmann on uteri obtained post mortem led these authors to describe as follows the anatomical changes that occur in the uterine mucous membrane at the time of the catamenial hæmorrhage. In the premenstrual epoch a round-cell infiltration occurs in the interglandular tissue, the lumina of the uterine glands become enlarged, and the bloodvessels dilated; subsequently, fatty degeneration of the superficial epithelium and the epithelium of the glands occurs, leading to laceration of the vessels and destruction of the affected area of tissue; after the cessation of the bleeding, regeneration of the mucous membrane occurs.

According to Gebhard, three stages may be distinguished. The first stage is that of premenstrual congestion, or stage of engorgement: the capillary vessels of the mucous membrane become distended with blood, the membrane itself becomes softened, the meshes of the stroma become enlarged and are filled with the morphological constituents of the blood, subepithelial hæmatomata are formed. The second stage is that in which the blood finds its way to the exterior: owing to the turgescence of the mucous membrane the blood is able to exude between the cells of the intact epithelium; further, the epithelium becomes lacerated in various places where hæmatomata have formed beneath it, allowing the blood to exude through the apertures thus formed; shreds of epithelium may be washed away by the blood-stream. The third stage is that of post-menstrual regeneration: the swelling of the mucous membrane disappears, the detached areas of epithelium readhere, the blood effused into the interstices of the tissue is reabsorbed, or is in part transformed into yellowish-brown flakes of pigment. According to Gebhard’s view, during menstruation destruction of the uterine mucous membrane does not occur. At no time is the membrane denuded of large areas of epithelium; a very active process of regeneration occurs, however, in the superficial epithelium and the epithelium of the glands, which fits the uterine mucosa for the reception of the fertilized ovum by keeping it in an ever-young and renovated condition. The mucous membrane of the cervix takes part in menstruation at most by an increased secretion of mucus.

According to Landau and Rheinstein, the mucous membrane of the Fallopian tubes contributes to the menstrual hæmorrhage; Fritsch and Strassmann, however, are opposed to the view that there is a regular tubal menstruation.

Pathology of Menstruation.