90 STUDIES ON PATHOLOGIC OVA. 



be shown to communicate with the surface by means of an epithelial invagination. 

 Most of them, however, lie isolated in the stroma. 



In looking about for a possible explanation for the presence of these vesicles, 

 it became evident that they had their origin in epithelial invaginations. The 

 opposite walls of these invaginations apparently become fused proximally and 

 their strands of epithelium then connect the vesicles with the surface. Further 

 examination of the sections of the villi in this specimen shows that instead of 

 having a fairly regular border, the epithelium is decidedly crenated or folded, quite 

 in contrast with the usual condition of things. Hence it would seem that prolifera- 

 tion of the epithelium has resulted in foldings into the stroma of the villus, instead 

 of accumulations on the surface. The presence of proliferation of the epithelium 

 in this case seems to lend further confirmation to the presence of hydatiform 

 degeneration. 



Out of 73 specimens originally placed in this group, 16 were found to belong 

 elsewhere, and 23 were added, making 80, from which 1 must be subtracted be- 

 cause of twins in one chorionic vesicle. The decidua was present in 45.5 per cent 

 and infiltrated in 88.9 per cent of these, excluding 2 in which infiltration was 

 doubtful. This infiltration was marked, even up to abscess formation, in 56.2 per 

 cent of the specimens and slight in the rest. Hydatiform degeneration was present 

 in 24 per cent, excluding 5 in which its occurrence was probable. Infiltration 

 was present in 90 per cent of the specimens in which the decidua was included 

 and not too necrotic for examination. 



In attempting to correlate the clinical histories with the objective examina- 

 tion, it was found that the clinical diagnosis of infection is confirmed in 4 out of 5 

 cases. In the fifth case the decidua was not included, but since hydatiform de- 

 generation was present, infiltration can be assumed and the clinical diagnosis of 

 infection be regarded as confirmed in this case also. Of the 6 cases which were 

 reported as showing no evidence of venereal disease, the decidua was not included 

 in one and was too degenerate to assist in the diagnosis in a second case. Of the 

 remaining 4 cases, 3 show the presence of a severe and 1 of a mild infiltration. 



Although mechanical interference with the course of the gestation seldom was 

 reported in this series, several specimens were noted in which abortion probably 

 was induced. In one case in which the termination of pregnancy was attributed 

 to fright, the decidua, unfortunately, was not included; but since the chorionic 

 vesicle showed hydatiform degeneration, the decidua undoubtedly was infiltrated. 

 In a second case in which fright was given as the alleged cause, Mall noted that 

 the decidua was "markedly inflamed. " In a third case, in which the termination 

 of pregnancy was attributed to work, death of the conceptus must have occurred 

 long before. As stated in the introduction, I fully realize that this contradiction 

 between the alleged cause and the findings may be apparent only, for it is entirely 

 possible that exertion, psychical disturbances, or an accident may precipitate an 

 abortion which is more or less imminent at the time. 



The structural changes encountered in this group do not differ in kind from 

 those present in previous groups. However, the incidence of infiltration of the 



