214 STUDIES ON PATHOLOGIC OVA. 



tion is a change which is exceedingly common in the earlier months of pregnancy, 

 just as measles is common in childhood, and that it becomes progressively less 

 common as the end of pregnancy is approached, just as does measles as senility 

 is approached. The obstetrician does not see most of the cases of hydatiform 

 degeneration, for they are merely reported as miscarriages and the specimens 

 often are destroyed or retained unrecognized by the general practitioner or the 

 midwife. They are often aborted spontaneously and completely with the decidua 

 and rarely are still contained in a closed decidual cast when they reach the lab- 

 oratory. 



The spontaneity of the abortion, especially in early cases, was emphasized 

 also by Storch (see page 208). Cortiguera (1906) is reported by Pazzi (1908 b ) 

 also to have declared that many moles disappear wholly without leaving a rem- 

 nant, even if occurring repeatedly in the same woman, and Donskoj (1911) also 

 stated that many of those aborted do not come to the attention of physicians 

 because of their harmlessness. This, however, does not imply that those which 

 persist and develop into large masses are equally harmless, and it must be remem- 

 bered that it is upon these that the current opinion regarding the tendencies to 

 malignancy of the hydatiform mole is based. 



The conclusion regarding the greater incidence of hydatiform degeneration in 

 the early months of pregnancy is conclusively confirmed by its occurrence in 33 

 of the 45 tubal specimens, within the first two classes of the pathologic division of 

 Mall, and in 100 of the 105 uterine specimens in the first six classes of this division. 

 Most of the specimens in these classes are composed of villi, of empty chorionic 

 vesicles, or of vesicles with embryos most of which have a length of less than 20 

 to 30 mm. That hydatiform degeneration is more common in the early months of 

 pregnancy is indicated also by the well-known reports of Kehrer (1894) on 50 

 cases, and of Borland and Gerson (1896), who found that 63 per cent of 100 cases 

 had aborted in the fourth and fifth months of pregnancy. According to Seitz, 

 Hirtzman (1874) also found that 62.8 per cent of 35 cases had aborted between 

 the third and six months. Only 2 of Kehrer's 50 cases, or 4 per cent, and only 3 

 per cent of the cases of Borland and Gerson aborted at the tenth month. Bonskoj 

 stated that 7 of the 10 cases reported by him aborted in the fourth month and 

 none after the sixth month. He stated further that 56 per cent of Bloch's 50 cases 

 aborted before the sixth month, 44 per cent later than this, one being retained 

 until the fourteenth month. The latter case is especially interesting, because 

 retention not only beyond term but after the death of the mole, seems to be re- 

 garded as relatively rare. This, however, does not imply that retention beyond 

 the period of growth of the hydatid mole does not occur, although Sternberg (1910), 

 who also emphasized the great rarity of this condition, erroneously stated that the 

 German literature reveals only a single instance of missed abortion in case of 

 hydatiform mole, viz, that of Poten (1901). In this case a hydatiform mole of 

 the size of a duck egg was said to have been aborted approximately one month 

 beyond term. Hence growth must have ceased long before and the mole have 

 remained in utero as a "harmless body." To this case of Poten, Sternberg added 



