Paper - A study of the causes underlying the origin of human monsters 9
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Mall FP. A study of the causes underlying the origin of human monsters. (1908) J Morphol. 19: 3-368.
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A Study Of The Causes Underlying The Origin Of Human Monsters
Unruptured Tubal Pregnancies
It is of interest to consider together the ova obtained from tubal pregnancies, for it is through them that light may be thrown upon the question, if the embryo is pathological, whether its condition is inherited or is due to the bad environment of the ovum. In case it is the former, the per cent of pathological embryos should not be larger than those obtained from the uterus; in case it is due to the latter, the per cent should be increased.
It is stated by different writers that embryos are rarely found in tubal pregnancies, but that remnants of the chorion are often present. However, it is also stated that, in case the tube is found ruptured and much blood has escaped into the peritoneal cavity, the embryo may have been present, but could not be found on account of the great quantity of blood. On the other hand, Professor Brodel informs me that among eleven specimens of tubal pregnancies found recorded in his catalogue of human embryos nine contained normal specimens. In my own collection seven tubal pregnancies out of nineteen specimens contained normal embryos. It must be remembered that as a rule specimens were sent to us only in case the surgeons who removed them found normal embryos, which they thought we were collecting. Considering only the tubes that were sent to me unopened and excluding those which were obtained from Dr. Ke'lly’s gynecological laboratory, I ﬁnd among seven specimens two ova without embryos, four with pathological embryos and but one with a normal embryo. The other six normal embryos spoken of above were all recognized by the surgeons as “normal and valuable specimens” before they came into my hands.
Following the hint obtained by considering all of the specimens which came to me unopened, I collected all of the histories of the same kind of specimens from Dr. Kelly's laboratory. These cover a period of about ten years and are taken from the laboratory records of over 10,000 miscellaneous cases. I ﬁnd that altogether I28 cases of tubal pregnancy were carefully described after numerous sections of them had been examined microscopically. I have excluded the reports of 82 of the specimens, for in them the tubes had ruptured before the operation. Of the 46 that remain the histories state that they were unruptured and vary from one to six centimeters in diameter. Two of the 46 contained normal embryos of the second month and ﬁve of them pathological embryos. The rest, 39 in number, contained entire ova without embryos or simply villi of the chorion in various stages of degeneration. Usually the dilated tube was found ﬁlled with blood through which were scattered villi, the chorion rarely being intact, that is, encircling the coelom. The chorion had collapsed, leaving scattered villi, which were "degenerated,” “poorly formed,” or “necrotic,” in different cases. Usually, it is stated in the record, “scattered villi were found in the clot; no embryo was found.”
The normal embryos need not be discussed more than to mention that the amnion was very small, as is usually the case in these specimens. The pathological specimens, however, are of the same nature and degree of degeneration as those found in the specimens obtained from the uterus. A number of small specimens which were cut into serial sections contained no embryos at all; they are included among the 39 mentioned above. From my experience in searching for embryos in pathological ova I am of the opinion that a few more pathological embryos would have been found had the specimens been examined with greater care. It is unlikely that more normal embryos would have been found, for in all cases they lie in a coelom or an amnion ﬁlled with a clear ﬂuid. I have never found a normal embryo in an ovum which did not contain a cavity well marked by a sharp wall and ﬁlled with a transparent ﬂuid, and therefore think it unlikely that those who made the sections for microscopical examination overlooked any normal embryos.
From my records not over seven per cent of uterine pregnancies contain pathological embryos andvwere the primary cause which produces them located in the germ we would not expect a higher per cent in ova from tubal pregnancies. Instead, we ﬁnd that 96 per cent are pathological and but 4 per cent normal (two in 46 specimens). Since this point is of prime importance in the causal study of terata, I have brought together all of the pathological ova I have obtained from tubal pregnancies. These have been studied with greater care, as a number of them have been cut into serial sections. Most of them will be found ﬁgured among the illustrations of this article. The following table shows that there are 14 specimens, of which seven contain pathological embryos and six are entirely free of them. Nearly all of the ova are very small, and in practically all of them the chorion is markedly affected. Generally the mesoderm of the chorion is fibrous and atrophic, the villi also showing all kinds and degrees of degeneration. Occasionally some of the villi are hypertrophic:
b Dime“; Condition of N“ "" ‘}§’f,‘j,§_ E“‘b"’°' Chorion and Remarks. mm IIIIII.
158 rz x 2, Vesicular Atrophic. _ 196 :2 x :2 3, I-Iomoge- Atrophic——Some villi axe en neous larged and invaded by syncytium. 298 4 None Fibrous villi partly inﬁltrated with leucocytes. 324 45 x 45 3.5 Atrophic. and ﬁbrous. No syncyt1um._ 342 30 x 20 5 Atrophic and ﬁbrous. 348 6, Atrophic 361 to None Coelom ﬁlled with a dense magma. 367 1 o x 7 None Villi degenerated in part. 369 7 x 3 None Villi ﬁbrous and degenerated. 3 78 1 2 None Villi oedematous. 396 7 2, Vesicular Mesoderm and villi ﬁbrous, some invasion by syncytium Plate II, Fig. 6 8 x 6 None Plate II, Fig. 5 6 Vesicular (.7) Plate II, Fig.-7 60 x 20 r 1 Chorion hypertrophic and em bryo disintegrating.
In most instances the coelo_m is ﬁlled with a dense magma and in six the embryo is entirely wanting.‘ The embryos in the remaining seven are of the vesicular form in three, of the cylindrical form in four, and are necrotic and disintegrating in the remaining specimens. In general, the changes in the chorion and embryo in these 14 specimens are the same as in those that are obtained from uterine pregnancies. It cannot possibly be admitted that the primary difﬁculty in these specimens is to be found in the embryo itself, that is, it is germinal, for the ova which become lodged in the tube are probably of an average kind, unless the unreasonable stand is taken that there is a greater tendency for abnormal than normal ova to lodge in the tube. To take this stand it is necessary to overlook altogether those cases in which tubal pregnancy is due to mechanical obstruction of, or to diverticula from the uterine tubes. The results obtained from the study of these I4 specimens are probably representative of all tubal pregnancies which are examined with great care before the tubes rupture. In the very earliest specimens there are indications of faulty implantation, due no doubt to the character of the tissue of the tube which permits of an excessive hemorrhage around the ovum (e. g., No. 396). Only in rare instances does a good decidua form in the tube, which in these cases must be produced by the presence of a growing ovum. However, just in these cases a decidua develops in the uterus, although the ovum is not present there.
I have found in collecting 434 human embryos of all kinds that 163 of them, or 38 per cent., are pathological. If we consider that an abortion occurs in every ﬁfth pregnancy, then a pathological ovum is found in every twelfth pregnancy (7 per cent in the table). If anything, this number is too high, for a number of larger normal foetuses were not catalogued and are not included with the total number—434. If the data obtained from unruptured tubal pregnancies where the number of pathological specimens rises to 96 per cent are compared with the pathological specimens from uterine pregnancies (7 per cent), it seems to me that the argument against the germinal origin of pathological ova and monsters is overwhelming.
The relation of the chorion to the wall of the tube or to the mucous membrane of the uterus is well known for ova two millimeters in diameter or larger. The two structures become beautifully adjusted, but in the case of most tubal pregnancies the small ova and villi ﬂoat largely in a mass of blood, are not adjusted to the decidua, and, apparently, on account of impaired nutrition, degenerate. The syncytium becomes atrophic, the villi become ﬁbrous, and often leucocytes as well as syncytial cells invade the mesoderin of the chorion. It naturally follows that when the nutrition of the ovum is impaired the most advanced growing point, the embryo, for which all is adjusted, should suffer most. Thus it happens that in many instances the chorion is not markedly changed, but the embryo is almost entirely destroyed or 15 wanting altogether. In a short time the.ovum collapses, becomes an irregular mass, and its “rootlets,” the villi, are still found scattered throughout the blo0d—clot, or a small heap of them are found poorly adjusted in a fold of the tube covered with changed and distorted syncytium and decidua. These conditions, found so well marked in tubal pregnancies, are also found in uterine pregnancies, but in them it is difficult to determine whether the degeneration of the chorion follows because the embryo has died suddenly or has inherited the power to become abnormal. The study of the ova from tubal pregnancies demonstrates conclusively, it seems to me, that the changes in the chorion are primary, and those in the embryo secondary, due to faulty implantation of the chorion.
Another argument in favor of the view I have advanced regarding the production of pathological embryos is obtained by studying those embryos in tubal pregnancies which were not destroyed at once, but which became well attached and grew on towards full term. I mean the fate of the 4 per cent of normal embryos found in early unruptured tubal pregnancies.