SPECIMENS COMPOSED OF VILLI ONLY. 55 



remnants of degenerated trophoblast and syncytium which remained were no 

 longer able to inhibit menstruation. Hence the decidua of pregnancy, together 

 with these few small remnants of the conceptus, was expelled in toto at the time of 

 onset of the next period, and it may be extremely significant that this occurred 

 exactly two menstrual months after the beginning of the last period. Since 3 

 other specimens of a series of 16, composed of villi only, were aborted at the time 

 of recurrence of the regular period, the idea that abortion occurs oftener at that 

 than at any other time would seem to receive some confirmation. Moreover, it 

 would appear quite natural that a decidua which has subserved its functions 

 would be more likely to be shed at this time and that an unabsorbed conceptus 

 which had been converted essentially into a foreign body should then be expelled. 



It is impossible to decide how far the development of this conceptus had 

 progressed before its death, but the extent of absorption shows beyond any doubt 

 that the latter would have been absolutely complete before the advent of the next 

 or third period had the second period also been inhibited. Since in the assumed 

 case the decidual cast then would have been expelled after the ovum had been 

 completely absorbed, this decidual cast might have directed attention to the possi- 

 bility of the existence of a tubal rather than a uterine pregnancy. In view of the 

 facts here revealed, such a sequence of events might well give the impression of 

 the existence of an early tubal pregnancy which had undergone spontaneous retro- 

 gression without ever having given rise to the characteristic symptoms. In this 

 connection I am reminded of the fact that gynecologists have been of the opinion 

 that some tubal pregnancies undergo spontaneous cure. In many of these cases 

 the healing probably follows tubal abortion, but specimens in this collection also 

 indicate the possibility of another sequence of events. In some instances, for 

 example, the small intratubal blood-clot in which a small conceptus becomes 

 enclosed at the time of hemorrhage seems to undergo reduction within the tube. 

 Under these circumstances the conceptus, which was separated from its implan- 

 tation site, may then undergo retrogression, maceration, disintegration, and finally 

 may be completely absorbed, and the tube heal. Nor does it seem impossible 

 that the chorionic vesicle may remain and undergo a similar fate within the tube 

 in cases in which the cyema alone is aborted. 



Of the 16 specimens finally classed in group 1, all of which were examined 

 both macroscopically and microscopically, 7, or 43.7 per cent, show hydatiform 

 degeneration. In each of these specimens the abortion very probably was not 

 induced. In 5 of these specimens in which some or all of the decidua accompanied 

 the specimen, it showed changes indicative of endometritis. In 4 of these the 

 infiltration was marked and in one it was slight. One specimen counted as showing 

 hydatiform changes was extremely degenerate, however, and unaccompanied by 

 decidua, and may therefore perhaps be rejected, thus leaving 6 specimens, or 37.5 

 per cent, definitely showing hydatiform degeneration. 



The decidua was included in 13 of the 16 specimens in this group, but the 

 material was very necrotic in one case and too little of it accompanied another. 

 The infiltration was slight in one of the remaining 11, and very marked in the other 



