A system of practical medicine. By American authors. Vol. 4

by Unknown

PATHOLOGY AND MORBID ANATOMY.—I have endeavored to describe with some accuracy the appearance of the healthy ovum, the sac, and surrounding structures during the various periods of early pregnancy, as it is the comparison with these which will enable the practitioner to distinguish between spontaneous and criminal abortion, enable him to determine the duration of pregnancy, guide him as to the cause, and thus serve to facilitate treatment and perhaps to prevent recurrence. Knowing what has been expelled, whether it is ovum and decidua entire or only in part, the line of action is evident. In all abortions due to an immediate and active exciting cause, whether criminal or resulting from shock or accidental trauma, the ovum is healthy, normal in all its parts, size and development of the embryo corresponding to the period of pregnancy at which the accident occurred; whilst in spontaneous abortions due to accidental causes more or less marked changes exist: the development of the embryo especially is retarded; its life has been destroyed, and growth has ceased, whilst the morbid development of the membranes continues, so that the mass expelled presents more or less of a mole formation—comparatively solid, with thick walls formed by the foetal membranes infiltrated with blood, the cavity often compressed by the surrounding extravasation, the embryo comparatively small or disintegrated in whole or in part.

The ovum is usually separated in its upper portion by hemorrhage, which comes from that point at which the vessels are most fully developed, the future placental site, though still agglutinated. With the inauguration of uterine contractions separation takes place at its lower pole by dilatation of the os, and retraction of the uterine walls from the ovum proper surrounded by the reflexa; as the abortion progresses, the muscular fibres of the fundus force it down into the dilating cervix through the still partially adherent decidua, and the intact ovum is expelled, the inverted decidua following it as the membranes do the placenta in labor at term. Yet these conditions vary greatly with the existing morbid changes.

In traumatic or criminal abortion the perfectly-formed ovum, the delicate cystic body surrounded by its shaggy chorion, is first expelled, to be followed by the decidua, usually—when in a healthy state—first by its anterior and then by its posterior half; whilst if the abortion has been inaugurated by some slowly-acting cause the decidua is hardened, infiltrated with compressed and clotted blood, the small ovum forming merely a part of the solid mass; and thus a firm oval body, coated with blood upon its rough, irregular exterior, appears.

Up to the third month the ovum is, as a rule, expelled as a whole, often even in the fourth. Later, unless decided pathological changes have taken place, the membranes are mostly ruptured and the embryo separately expelled, as in labor at term. In later months this is always the case, and the progress of abortion is greatly impaired by the adherent tissues: the mass of the ovum, which serves so much to excite uterine contractions and promote expulsion, is destroyed by the collapse of the amniotic sac, and separation and expulsion of the membranes are hindered by reason of the smaller amount of resistance offered. Hemorrhage is most likely to occur in the villi of the chorion, between its tissues and the surrounding decidua; if occurring in the latter structure, it appears thick, hard, infiltrated with blood, and no longer presents that soft, succulent appearance, but is firm and brittle.

The ovum as expelled presents three typical forms: First, as above stated, in accidentally-occurring traumatic or criminal abortion we find a healthy ovum with its shaggy chorion, and the inverted decidua attached or soon following, usually in two sections; most common, however, and almost without exception in spontaneous non-criminal abortion, is the mole formation, rarely the hydatiform mole, which has been described, and results only from the peculiar pathological condition of the chorion. The common form is the flesh mole, the mola carnosa, characteristic in appearance, resembling a polypoid growth, a reddish oval or rather pyriform mass with shreds of tissue (the decidua) adherent to its larger upper extremity, darker clots at the elongated lower pole. Upon section the walls show a brittle reddish structure, that of compressed and inspissated coagula, and in the centre a cavity containing fluid and detritus, if not the embryo, lined with a delicate membrane, amnion or amnion and chorion: the shape of the cavity is rather irregular by reason of the bulging protuberances formed by the contraction of the inspissated mass of blood extravasated between or within the tissues. These moles have very much the appearance of uterine polypi, and are often considered as such by physicians who pride themselves greatly upon curing their patients of tumors and the accompanying hemorrhage by a few doses of ergot. Though the macroscopic resemblance is such as to be quite deceptive, the mole upon section will always reveal a cavity, even if very small, containing fluid; and this cavity reveals the above-described characteristic slight bulging protuberances lined with a delicate membrane; whilst the microscopic examination shows the firm walls to consist of nothing but blood-corpuscles: the outer covering, often thoroughly infiltrated with blood, consists of the decidua serotina and reflexa, with more or less of the infiltrated shreds of the vera usually pendent from its upper extremity; when floated in water and cleansed, the outer or uterine surface of these shreds is ragged, rough, often appearing somewhat like the villi of the chorion, hence looked upon as placenta; this peculiar appearance is caused by the torn tissue in the line of demarcation in the lower or central meshy layer of the decidua vera, where it is separated from the lowest layer which remains adherent to the uterine wall. The inner surface toward the ovum will show a slightly wavy, cribriform appearance, the openings of the ducts appearing as fine depressions in the surface. (It must be remembered that this smooth inner surface is in the expelled specimen generally the outer one, as the decidua follows the ovum mostly as the membranes do the placenta at term—inverted.) If the disturbance causing the abortion has been of rapid progress, the cavity is large, the embryo approximating in development the period of expulsion; whilst if the changes have taken place slowly, the walls are thick, the cavity small, and the embryo may appear merely as a small mass pendent from the navel-string, or may have entirely disappeared, and can be traced only by the fine detritus in the amniotic fluid, the cord itself perhaps only in part remaining, and even this may have disappeared. The cavity will always be found toward the pendent pole of the decidua reflexa, as the extravasation takes place mainly in the serotina, giving it the appearance of a thick mass of clotted, compressed blood, and forcing the cavity toward the opposite extremity. These moles are usually more elongated and pyriform, one or two inches in diameter at their upper or larger extremity, three or four inches in length, with a greatly elongated and narrowed lower end, which has been so formed by being first wedged into the slowly-distending cervix.

Such is the appearance in those cases of slow progress in which death of the embryo has probably occurred at an early stage and hemorrhage has been the exciting factor, whether due to disease of the mother or other causes that may have destroyed the vitality of the germ. When resulting from disease of the mucous membrane, especially endometritis or catarrhal affections, it is a more oval tough mass, the main part of which is formed by the thickened and indurated vera; and if this be opened the ovum, in a very early stage of development, will be found within.

The uterus itself presents very much the appearance of the organ after labor; the external os, however, closes more rapidly, less rarely showing the funnel-shaped appearance of the puerperium; the cervix, though somewhat enlarged, is normal in appearance; the cavity is lined by the lower layer of the decidua, soft shreds covered with coagula; but it is lacking in the placental site and the putrid thrombi visible in labor at term.

Involution is slow if we take into consideration the slight distension of the uterus as compared to the process after delivery at term. The organ is in a state of healthy development, not prepared for the following retrograde metamorphosis, unless the expulsion of the ovum has been due to local disease, when some retrograde changes may have been inaugurated; if it results from constitutional causes, the existing depression naturally interferes with restitution. If shreds of tissue, parts of ovum, or decidua remain, absorption or expulsion is retarded. As a morbid or atonic condition so often exists, at least in abortion consequent upon natural causes, subinvolution or inflammatory conditions of the organ itself or the surrounding tissues are hence a frequent sequence.

SYMPTOMATOLOGY.—It will be remembered that abortion is more likely to occur among multigravidæ on account of the greater frequency of disease, especially pelvic affections; that it is most likely to accompany the periodic congestion which recurs at the time of expected menstruation; that it is more frequent in early married life, on account of the greater liability to traumatic injury and the existing nervous disturbance, and toward the menopause in that state of nervous and physical disturbance and lessening uterine activity. The third or fourth month of gestation is the dangerous period, as it is one of change of nutrition for the ovum, of the highest development of the decidua, and intense activity and congestion of the chorion, the rapidly-sprouting vessels finding but little resistance in the embryonic structures of the villi which surround them. Chronic disease of the mother is more likely to interfere with gestation at a later period; and, when knowingly undertaken with criminal intent, the time of choice is either the first month, when the first indications of pregnancy become evident and the menstrual period does not appear at the usual time, or more commonly at the time for reappearance of the third menstrual flow, when the fact of conception has been established to a certainty, and the conscious mother, firm in the belief of the nonviability of the embryo before the fourth month, thinks it harmless to rid herself of the ovum, which she considers a mere growth without life or soul, while she would shrink from destroying what, at a later period, she calls a living being.

SYMPTOMS AND COURSE OF ABORTION.—General Remarks: Preliminary Symptoms.—1. Course of early abortion, first two months.