SOME ASPECTS OF ABORTION. 353 



suggest that abortion not infrequently follows too closely repeated pregnancies, 

 especially under the stress of advancing years. 



If the condition of the uterine mucosa at the time of implantation of the 

 impregnated ovum may show variations in structure at all comparable to those 

 seen in deciduse accompanying abortuses, then it is easily conceivable that the 

 fate of the conceptus may be determined by the structure of the implantation 

 site. Not infrequently a small area of the decidua about an abortus shows all 

 the transitions shown in figures 75, 76, 77 (plate 6, Chap. IV), and 135 (plate 13, 

 Chap. IX). The first figure shows the fine, clear, large, potygonal decidual cells, 

 practically wholly infiltrated, and hence presents a rather homogeneous appearance. 

 Figure 76 shows considerable infiltration and autolysis, and also marked change 

 from the usual polygonal cell found present in the post-menstruum by Hitschmann 

 and Adler (1908) to a fibroblast form. In figure 78 (plate 6, Chap. IV) the normal 

 decidual cells have become still more elongated, and in figure 135 the decidua is 

 represented by a decidedly fibrous mass totally different from what it once was. 

 I do not know how far these changes of fibrosis of the decidua may have progressed 

 before implantation occurred, but if the changes in the mucosa are at all pro- 

 nounced, one scarcely can believe that they can fail to profoundly affect the nutri- 

 tion and growth of the conceptus. 



It may be urged that fibrosis of the decidua is but an effect of the death and 

 retention of the conceptus rather than an indication of the pathologic conditions 

 pre-existent in the mucosa. However, the many instances of abortuses in which 

 the decidua is very degenerate and also infiltrated would seem to argue against 

 such an assumption. Besides, many of the decidua? found surrounding retained 

 specimens do not show comparable changes. Moreover, Orloff (1896), Iwanoff 

 (1898), and L. Fraenkel (1903, 1910 b ) found that restoration of the mucosa may 

 begin before the conceptus is expelled from the uterus. This fact also seems to 

 suggest that fibrosis probably is pathologic in significance. Moreover, in the 

 few cases of partial regeneration of the mucosa which came to my attention, the 

 decidua was not in the fibrous state shown in figure 135. Infiltration of the 

 decidua no doubt more frequently might arise after death of the conceptus, but 

 that it frequently is present long before this time would seem to be indicated 

 also by the fact that the presence of fibrosis does not seem to bear any definite 

 relation to the duration of the retention, and that the condition of the mucosa 

 before implantation can markedly influence the course of gestation is indicated also 

 by the findings of Punto (1906) in cases of pregnancy complicated by myomata. 



